Work calendars are a point of contention amongst Bonsai practitioners. On the one hand there are those who say that “You don’t work on a tree based on the calendar.” and then others who say “You don’t do that particular work this time of year.” or “You should do x in spring.”
Our goal with presenting a work calendar is not to provide a rigid “rule” that x, y or z technique must be applied to a tree precisely at a set time. Instead, we hope to provide general guidance about the types of work that might be done in a general season. If the precise dates mentioned here work for you then that is great.
Either way, it’s useful to ask others about “Why” this work is done generally in these various seasons and months. Are you waiting for buds to appear? Flowers to drop? Temperatures to rise? Temperatures to lower? Ultimately, your personal bonsai calendar is going to be driven by your trees and your yard’s micro climate, but hopefully the work calendars below can help you get some insight into the work that is coming up and to plan and ask the questions you may need to ensure the work you do is the most beneficial to your tree and impactful to your goal.
For beginners or those learning a new species, we recommend that you pay attention to the types of activities that are performed during the year. Begin to build your own framework, ask: Why is this work done at all? What does it accomplish? How does the tree respond? Is it temperature sensitive? Is it timing sensitive?, etc.
The two primary drivers of Bonsai work are Growth & Goals
Growth is the unavoidable constant of Bonsai. The first category of growth is roots and leaves and their yearly cycle. The second category is energy management. Many would say the primary driver of growth is temperature, but temperature is really a leading indicator and it is arguable that length of daylight is even more critical than temperature. Ultimately the effect of length of day, and temperature, on the tree relates to rate of growth. In the North Georgia climate, in general, most trees wake up in the spring and go dormant in the fall.
All trees grow strongest when the day is longer, but may want the intensity of sun to be moderated or increased, while many deciduous actually have a mini dormancy in high heat and tropical trees thrive at the height of the hot summer. Suffice to say, it’s complicated and this complication is often the source of wisdom from folks who say “You can’t base Bonsai work on a calendar, you have to talk to the tree and listen to it!” This is true, but should you be asking your trees in Georgia whether they intend to sprout leaves on January 1st? No.
Goals are your vision for the tree. The first category of goals is horticultural health and the second goal is artistic. Horticultural health is the prime directive of Bonsai. A dead tree will never fulfill your vision and sometimes the answer to a vexing artistic question is to wait and let the tree be a tree. That’s why a lot of work below focuses on fertilizer (nutrients = health = growth) and insect control and fungus control. We have times of the year where these things are most problematic, but you have to keep a watchful eye.
Artistic goals can also be categorized a million ways, but for the sake of this article I’m going to simplify things. On one hand we want to do some work as early in the year as possible to get multiple flushes out of a tree in the year. On the other hand some work is done right as things happen in the tree because the tree reacts negatively other times of the year or responds sub-optimally. In other cases, we want to manage sap flow. In other cases we want to redirect energy.
The artistic management of energy and growth is highly subjective and highly dependent on your own schedule. Just bear in mind that repotting, pinching, pruning, branch selection and just about everything we do artistically including wiring also has an effect on growth and health. The timing of this work is often timed to maintain the health and season cycle of the tree while also accomplishing the artistic goal. The timing is often not chosen because it’s actually the only time the work can be done. The same work can often be done just fine in other season if you learn techniques to maintain health or are willing to accept other tradeoffs.
Below, we’ve included sample work calendars. More general calendars from the web and the work of a club member focused on our region. This page is open for comments and we’d love your insight and experience if you have it to share.
Work Calendars
Work Calendars on the Web
- Bonsai Empire – good general overview
- National Bonsai Society – work overview calendar
- Bonsai Tonight – creating your own bonsai calendar – a touch of the Bonsai Empire calendar, a dash of Ted’s and your own experience will get you well on the way to developing your own calendar.
Ted’s Work Calendar
Ted Groszkiewiczby was a member of the Atlanta Bonsai Society a ways back. He worked to formalize a calendar of work and the below is the result. Many people say the calendar is out of date. That certain techniques are not done at the time that Ted recommended and that as our local climate has trended warmer activities like repotting are often done earlier in the year. Other people have built their own adjusted calendar using Ted’s as a road map, but not a set of rules. We present the calendar here as a historical club artifact, a way to see a good corpus of the work that could be performed in a year, and at least a not entirely irrational timing of activities in our area.
January
Transplanting
If you missed root-pruning and transplanting your Chinese Quince (October – December), you can do so this month if normal bud activity begins.
Prune & Trim
Apple, Crape Myrtle, Maples, Pines – black and white, Japanese Quince – after flowering, Spruce, Sweetgum.
Wire
Cedar, Chamaecyparis – Hinoki, Cryptomeria, Fir, Pines – all, Podacarpus, Spruce, Yew.
Fertilize
Citrus in a greenhouse environment.
Notes
This month you need to prepare for the activities in forthcoming months. A large calendar with spaces each day of the month is excellent. Place it where you can see it easily as a reminder of bonsai things to do. List the things to do on the calendar and then follow through. By using a calendar, you can pace yourself to do all the necessary preliminary tasks and you won’t be overburdened during the very busy months of March, April and May.
If you haven’t applied a dormant spray in late fall, do so now. You can use either refined oil or lime sulfur on you evergreens and deciduous plants. Refined oil is recommended for broad-leafed evergreens and conifers (pines, juniper, cedar) and is easier to use. Follow directions on the label and do not exceed recommended formula. This is an excellent control for over-wintering pests and fungi.
Wash all containers that were used in training and growing bonsai. Use a mild laundry detergent, rinse thoroughly with clean water, and then soak for 10 minutes in a household bleach (not scented) solution of 1 part bleach to 9 parts of water. This is a strong solution, so do use plastic gloves or a pair of tongs when placing containers into the bleach solution and removing them from the solution. This soaking sanitizes the container and will kill any fungi which may have contaminated the container.
Prepare soil mixes for your potting and re-potting in the next few months. On nice, warm days, you can re-shape your deciduous trees with light pruning.If you have wired any bonsai in the late fall, you should check to make certain the wires are not too tight. Even though trees are dormant, there is a certain amount of growth that takes place. Remove the wires if you see signs of wire damage to the bark.
Mid-January is an excellent time to graft fruiting trees and pines. This is a good method of propagating plant material that does not readily strike roots from cuttings or air layering. Seal the grafts and give protection from freezing during the remainder of the winter. Collect moss and store it in a suitable location (cool shady area) in your garden for use in later months for potting and re-potting.
Photograph trees in winter silhouette for later training. It is much easier to see the structure of deciduous trees without foliate. Use the photographs for re-shaping or changing your design during the growing season. Plan collecting trips to middle and south Georgia in February. Collect native trees in North Georgia during March. Cold winter winds can cause soil in containers to dry out very quickly. Be certain to water your trees after several windy days without any rain. To be certain, check the soil in containers at least once each week.
February
Transplant / Prune
Almond – after flowering, Apple – as buds begin to appear, Apricot – after flowering, Bald Cypress – when leaf buds just begin to show color, Cherry – after flowering, Crabapple – as buds begin to appear, Plum, after flowering, Quince – Chinese when normal bud activity begins, Redbud – as flower buds appear, Zelkova – when leaf buds begin to show green color. During the last week of February you can re-pot and root prune early sprouting species of deciduous trees such as the Japanese maple “Kiyo Hime” and western maple “Amur.”
Prune & Trim
Apple, Bald Cypress ONLY when actively in growth with new foliage out to the top of the branch or if dormant and the branch is at least 1/2″ in
diameter (pinkie size), Crape Myrtle, Juniper, Pine – red/white, Quince – Japanese after flowering, Spruce, Sweetgum.
Wire
Bald Cypress, Cedar, Chamaecyparis – Hinoki, Cryptomeria, Cypress, Fir, Juniper, Pines – all Podocarpus, Spruce, Yew.
Fertilize
None
Notes
Continue planning for the busy months ahead. If you haven’t used dormant sprays last month, do so this month. Do not use dormant sprays if a freezing condition is anticipated within 24 hours. Plan and scout out areas for collecting native material in north Georgia. Collecting this month in middle and south Georgia is okay. Be certain to get owner’s permission before collecting plant material. Take special care in watering. Do not water when soil is frozen. Wait for warmer weather and then water thoroughly during morning hours before the next freeze sets in. Wait to pot up flowering trees such as Apricot, Plum, etc. Enjoy the flowers. However, don’t hold off until tiny leaves showing. That’ too late to root prune.
You can start to prune fruiting trees this month. See above for re-potting and root pruning flowering trees. Much depends on local weather conditions.If you want to try your skill at grafting pines and conifers, they can still be grafted this month. You can also start grafting deciduous trees late in the month.
If you haven’t prepared a supply of bonsai soil mix for your trees, do so this month. Otherwise, you will be caught in the middle of your very busy re-potting activity playing “catch-up” or “catch as catch can” in providing soil mixes for your bonsai. Preparing soil mixes now will save you time and frustration in the months to follow. Don’t delay.
Mix up your soil now. Keep an attentive eye on the weather. In late February it is possible to start re-potting, but check your trees closely. If buds begin to swell on deciduous trees and there is no danger of freezing for several days, you can transplant and root prune.
Caution – Watch the long-range weather forecasts and don’t be too hasty to root prune or re-pot if forecasts call for continued freezes and below-normal conditions. Take the time this month to clean and sharpen your bonsai tools. The months ahead will call for much use of scissors, pruners, knives, chisels or carving tools. A sharp tool can prevent injury by cutting wood cleanly instead of jamming or slipping and causing accidental injury.
March
Transplant / Prune
Almond – after flowering, Apple – as buds begin to appear, Apricot – after flowering, Azalea – after flowering, Bald Cypress – when leaf buds begin to show color, Beech – before buds come out, Birch – as new leaves appear, Camellia, Cedar, Chamaecyparis – Hinoki, Cherry, Cotoneaster, Crabapple – as buds begin to appear, Cryptomeria, Cypress, Elm, Fig (ficus), Ginkgo, Hackberry, Hawthorn, Hemlock, Holly – all, Honey Locust – as new shoots appear, Hornbeam – before buds come out, Jasmine (winter) – after flowering, Juniper, Maples – all, Pear, Peach, Persimmon, Pines – all, Plum – after flowering, Podocarpus, Pomegranate, Privet, Pyracantha, Redbud – as flowers begin to appear, Serviceberry – before buds open, Spruce, Sweetgum – as new buds open, Zelkova, Witch Hazel – before leaf buds open, Wisteria – after flowering, Yew.
Prune & Trim
Apple, Azalea – after flowering, Apricot 2/3 after flowering, Bald Cypress 0 only when actively in growth with green foliage to the top or branch (or when dormant and the branch is at least 1/2 inch in diameter – pinkie size), Cedar, Camellia, Cotoneaster, Cryptomeria, Cypress, Elm, Fig (ficus), Hawthorn, Hemlock,
Holly – all, Hornbeam, Juniper, Maples – all, Mountain Laurel, Nandina – if old canes are too long, Pear, Pines – all, Privet, Plum – 2/3 after flowering, Quince (Japanese) – after flowering, Sasanqua, Spruce, Sweetgum, Wisteria, Yew, Zelkova.
Trim/Pinch New Growth:
Azalea – pinch new soft growth until June 15, Bald Cypress only when actively in growth with leaves to the top of the branch, Beech – only new growth is trimmed in the spring; wait until new buds have elongated to where you can see individual leaves and then trim back leaving 2 to 3 leaves. Crabapple – trim new soft shoots, Hackberry – after new 3-5 nodes leaving one or two nodes – anytime during the growing season, Hawthorn – prune new soft shoots.
Wire
Bald Cypress, Cotoneaster, Crabapple, Fir, Pomegranate, Privet, Pyracantha, Quince – Japanese, Spruce.
Fertilize
Cedar, Chamaecyparis – Hinoki, Cherry, Cryptomeria, Cypress, Juniper, Peach, Pine – cork bark, Pomegranate.
Notes
This month is the beginning of concentrated bonsai activity. It is (depending on weather conditions) the start of a new growth cycle. Check your trees carefully for indication of new growth. For deciduous trees, the best time to re-pot, transplant and root prune (if necessary) is when the buds begin to swell and before the emergence of new leaves.
Caution: It is better to be a little early than late.
Check condition of your bonsai prior to root pruning. There is no need to root prune if the roots are not pod-bound (masses of roots pushing against the sides of the container) and roots indicate healthy growth (white root tips).
Remember that root pruning will induce new growth below and above soil level and could drastically change the shape and design of your bonsai. However, a change of soil and re-potting (without root pruning) can be beneficial to the health of your bonsai. If you are potting your bonsai for the first time into a bonsai container, you will have to root prune to reduce the root mass to fit the container. The new top growth this procedure will induce can be controlled by pruning and pinching during the growing season.
Re-potted and root-pruned bonsai should be placed in a shady area for at least two weeks. After two weeks the trees can be gradually be brought out into full light and your normal display area. Fertilizer should be withheld for at least six weeks to allow new roots to grow into the new soil. After the six-week period, you can start a regular fertilizer program. Top pruning and wiring, if called for in the schedule, should be done prior to re-potting or root pruning. March is also an excellent month to collect native plant material in North Georgia to add to your growing bonsai collection. Depending on weather conditions, insect activity could begin this month. Use appropriate insecticide to control any intense activity. Read manufacturer’s label and use prescribed dosage. Too much is not better and could be injurious to your bonsai and to your health.
Your display benches should be scrubbed and painted with a wood preservative. You can clean your benches with 1 part household bleach to 9 parts of water to kill fungi, mold and algae. You can use a pump type pressure sprayer to spray the solution and let stand for 5 to 10 minutes. Scrubbing with a brush may be necessary for stubborn areas. Rinse thoroughly with clean water. When completely dry, apply a wood preservative, even over treated wood, to prevent early decay. As with any chemical to be used around plants, read wood preservative label before using.
April
Transplant / Prune
Almond – after flowering, Apple – as buds begin to appear, Apricot – after flowering, Azalea, Bald Cypress when new buds begin to show leaf color, Beech, Birch, Boxwood, Camellia, Cedar, Cherry – after flowering, Chamaecyparis – Hinoki, Cotoneaster, Citrus, Crabapple – as buds begin to appear, Crape Myrtle, Cryptomeria, Cypress, Elaeagnus – as buds come out, Fig (ficus), Fir, Gardenia, Hemlock, Hornbeam, Juniper, Mountain Laurel – after flowers wither and leaf buds appear,Nandina, Oak, Persimmon, Pine – black/red/cord bark, Plum – after flowering, Podacarpus, Pomegranate, Privet, Pyracantha, Redbud – as flower buds open, Rhododendron, Sasanqua, Spruce, Sweetgum – as new buds appear, Tamarix, Weeping Willow, Yew, Zelkova.ond – after flowering, Apple – as buds begin to appear, Apricot – after flowering, Bald Cypress – when leaf buds just begin to show color, Cherry – after flowering, Crabapple – as buds begin to appear, Plum, after flowering, Quince – Chinese when normal bud activity begins, Redbud – as flower buds appear, Zelkova – when leaf buds begin to show green color. During the last week of February you can re-pot and root prune early sprouting species of deciduous trees such as the Japanese maple “Kiyo Hime” and western maple “Amur.”
Prune & Trim
Apple, Apricot – after flowering, Azalea – after flowering, Bald Cypress – prune branches ONLY when in active growth; new leaves out to the tip or when dormant if the branch is at least 1/2” diameter (pinkie size); if in doubt – don’t prune. Boxwood, Camellia, Citrus, Cotoneaster, Crabapple – after flowering, Fig (ficus), Fir, Gardenia, Honey Locust – after blossoms appear, Hemlock, Nandina – old canes that are too long, Oak, Peach, Pear, Privet, Rhododendron, Serviceberry – after flowering, Tamarix.
Trim/Pinch New Growth:
Azalea – pinch/trim new soft growth until end of June. Bald Cypress – only when in active growth (see above), Beech – pinch new shoots while still soft leaving 1-2 nodes, Birch, Boxwood, Camellia – pinch tips after leaves have hardened, Cedar, Chamaecyparis – Hinoki, Citrus, Cotoneaster – pinch/trim new soft growth leaving 2 pairs of leaves, Crabapple – pinch/trim new shoots, Crape Myrtle, Cryptomeria, Cypress, Elm, Ginko, Hackberry – trim after new shoots have 3-5 nodes during growing season – leave 1-2 nodes, Hawthorn – pinch/trim new shoots, Holly – all, Honey Locust – trim elongated shoots leaving 1 or 2 nodes, Hornbeam – elongated shoots to desired shape until summer, Juniper, Maples – all, Mountain Laurel – trim after shoots have hardened leaving 2-3 leaves, Oak, Pines – Cork bark/Red, Podacarpus, Pomegranate – trim new long soft growth, Pyracantha – pinch/trim new shoots leave 2 pairs of leaves, Chinese Quince, Sasanqua – pinch tips after leaves have hardened, Serviceberry – after leaves harden pinch off tips of shoots, Spruce, Sweetgum, Willow, Wysteria – trim with scissors after blossom withers but before new buds harden, Yew, Zelkova.
Wire
Bald Cypress, Cedar, Cotoneaster, Crabapple, Eleagnus, Hackberry – after shoots harden, Pomegranate, Privet, Pyracantha, Quince – Japanese, Weeping Willow – only heavy branches before buds come out, Wisteria – wire to shape as new buds appear, Witch Hazel – before buds open.
Fertilize
If you fertilize before the 20th of this month, use a weak water-soluble solution or a very low or 0 nitrogen fertilizer to avoid early top growth which could be damaged by late frosts which are common in zones 7/8 prior to April 20.Apple, Azalea, Bald Cypress, Beech, Birch, Camellia, Cedar, Cherry, Citrus, Cotoneaster, Crabapple, Cryptomeria, Chamaecyparis – Hinoki, Cypress, Elm, Fir, Gardenia, Ginko, Hawthorn, Hemlock, Hornbeam, Juniper, Maples, Nandina, Oak, Peach, Pear, Persimmon, Pines – all, Podacarpus, Pomegranate, Privet, Pyracantha, Quince, Rhododendron, Sasanqua, Spruce, Sweetgum, Willow, Yew, Zelkova.
Notes
This month continues the activity of bonsai culture with re-potting, first potting, root pruning (if necessary), trimming and pinching new growth as well as wiring for shape and design as desired by the owner. Keep a close check on any trees which may have been wired over winter. Tissue will begin to swell rapidly and wire must be removed before the bark is damaged. As the temperature warms up, insect activity will start up. Check on pest activity frequently and use the appropriate insecticide before damage occurs. If you haven’t prepared your outdoor bonsai area, do so before April 20 (last freeze date). Clean and remove mildew from your benches or shelves by scrubbing them with a solution of 1 part household bleach to 9 parts of water. Rinse with clean water and allow to dry thoroughly. If necessary, treat your benches or shelves with a wood preservative. Read wood preservative label thoroughly before using it on your display benches. Check wiring left on trees over the winter and remove if too tight and/or if the wire has done its job successfully. Do not place plants on benches or on any other raised area above the ground until after April 20th. In this climate zone, freezing temperatures are still possible at night. Historically, the last freeze date in the Atlanta area is April 25, 1910, so don’t be in a hurry to place your bonsai in display areas!
May
Transplant / Prune
Azalea – after flowering, Bamboo, Boxwood, Buttonwood, Camellia, Cedar, Citrus, Cotoneaster, Crape Myrtle, Cryptomeria, Gardenia – as new buds appear,
Hemlock, Juniper, Mountain Laurel – after flowers wither and new leaf buds appear, Pine – black/red, Pyracantha, Podacarpus, Sasanqua, Spruce, Tropicals, Willow, Yew.
Prune & Trim
Azalea – after flowering, Bald Cypress, Boxwood, Buttonwood, Cedar, Camellia, Cherry – 2/3 after flowering, Cotoneaster, Crabapple – after flowering, Cryptomeria, Elm, Gardenia, Hawthorn – after flowering season is over, Mountain Laurel, Persimmon, Pomegranate, Rhododendron, Sasanqua, Tropicals.
Trim
New Growth: Apple – trim after new shoots lengthen to 2-3 nodes leaving 1-2 nodes, Azalea – after flowering pinch/trim new growth until end of June, Bald Cypress, Beech – trim soft growth leaving 2 leaves, Birch – trim after soft growth elongates to 5-7 nodes leaving 1-2 nodes, Bamboo – trim close to the ground, Camellia – trim tips after leaves have hardened, Cedar – trim back new soft shoots continually, Citrus, Chamaecyparis – Hinoki – trim off extending tips and clean out interior, Cotoneaster – trim all new growth leaving 2 pairs of leaves, Crabapple – trim new shoots, Crape Myrtle – trim hard after initial growth produces flowers on smaller branches, Cryptomeria – trim off tips of primary and secondary shoots continually, Cypress – trim new soft extended growth continuously, Elm – trim all new growth leaving 2 leaves, Fig (Ficus), Gardenia – trim shoots after they have lengthened to 3-5 nodes leaving 1 or 2 nodes, Gingko – pinch/trim new soft growth leaving 2 leaves, Hemlock, Hawthorn – cut terminals, Holly – all, Honey Locust – trim elongated shoots to 1 or 2 nodes, Hornbeam – trim new growth leaving 2 leaves, Juniper – trim off tips of primary and secondary shoots continually, Maples – all – pinch/trim soft new growth on all twigs, leaving 2-3 sets of leaves, Mountain Laurel – trim after new shoots harden leaving 2-3 leaves, Oak, Pines – Cork bark/red/white, Podacarpus -trim back soft shoots continually, Pomegranate – as new shoots lengthen trim to leave 1 or 2 nodes – after secondary buds lengthen pinch back growth through June, Redbud – trim tips after leaves harden, Sasanqua, Spruce, Sweetgum, Tropicals, Willow, Wisteria, Yew – pinch/trim soft shoots continually, Zelkova – trim new soft growth leaving 2 leaves, Willow, Yew – trim out new growth anytime during the growing season.
Leaf Prune:
Make certain your trees are healthy and fertilize them at least 2 weeks before leaf pruning. Apple, Elm, Maple – all, Zelkova.
Wire
Apricot, Bald Cypress, Beech – as twigs harden – remove in 3 months, Boxwood, Camellia – as soon as shoots are woody, Cherry Crabapple, Cryptomeria,
Cotoneaster, Elaeagnus, Elm, Fig (ficus), Gardenia, Hackberry, Holly – all – new growth only – old wood too brittle, Mountain Laurel – after shoots harden, Pear, Persimmon – when leaves harden – removes wires in autumn, Plum, Podacarpus, Pomegranate, Privet, Pyracantha, Quince – Japanese, Redbud – after shoots begin to harden, Sasanqua – as soon as shoots are woody, Tamarix, Tropicals, Wisteria.
Fertilize
Apple, Apricot, Bald Cypress, Bamboo, Beech, Boxwood, Buttonwood, Camellia, Cedar, Citrus, Chamaecyparis – Hinoki, Cotoneaster, Crabapple, Crape Myrtle, Cryptomeria, Elm, Fig (ficus), Gardenia, Gingko, Hawthorn, Hemlock, Holly – deciduous, Hornbeam, Maples, Nandina, Oak, Pear, Persimmon, Pine – red/white, Plum, Podacarpus, Quince, Rhododendron, Sasanqua, Tropicals, Willow, Wisteria, Yew, Zelkova.
Notes
A very active month for bonsai enthusiasts. Bonsai can be set up safely on display benches or shelves outdoors. As the days get warmer,, growth will increase. Water young, rapid growing trees frequently, however, water older trees sparingly to keep foliage in scale with the size of the bonsai. This is particularly true if you plan on showing your trees this month and in June. If the trees are in training, they should be fertilized at least twice during this month except for conifers. If the trees have been pruned to shape, fertilize only once to maintain health without rapid, lush growth. Please see section “Fertilize” above. Re-potting and first-time potting continues this month. More attention should be paid to pinching and trimming this month to prevent long internodes on trees such as maples, elms, beech, hornbeam and sweetgum. Rotate tender leafed trees (as above) between shade and sun to prevent sun scorch. Check your wiring often during the growing season (through July and even into August). Don’t let the wire cut into the bark of your trees. It could cause permanent scars on your tender-bark trees such as azaleas, elms and maples. Insects will be more active this month. Be aware of these pests and use the appropriate insecticides when necessary. For safety and health reasons, follow manufacturer’s label instructions explicitly. Don’t take chances with the “more is better” reasoning. Junipers and cypress should be pinched heavily to promote dense growth.
June
Transplant / Prune
Azalea – after flowering, Buttonwood, Citrus, Cotoneaster, Tropicals, Wisteria.
Prune & Trim
Azalea – after flowering, Bald Cypress, Birch, Buttonwood, Cedar, Cryptomeria, Tropicals, Wisteria.Trim/Pinch New Growth: Apple, Azalea – after flowering pinch/trim new growth until the end of June, Bald Cypress, Birch – trim soft growth leaving 2 leaves, Camellia, Cedar -trim soft shoots continually, amaecyparis – Hinoki – trim out extending new growth, Citrus, Cryptomeria – trim out tips of primary and secondary shoots, Cypress – trim out extending new growth, Elm -trim new soft growth leaving 2 leaves, Fig (ficus), Fir, Gardenia, Ginko, trim new growth leaving 2 leaves; use sterile tools, Hemlock, Holly – all, Hornbeam, Jasmine – winter – trim primary shoots, Juniper – pinch off tips of primary and secondary shoots, Maple – all- trim new soft growth leaving 2 leaves, Mountain Laurel, Oak, Peach, Pine – black, Pine – white, Podocarpus – trim back soft shoots continually, Pomegranate – trim new long soft growth, Quince – Chinese – trim soft new growth until June 15, Spruce – twist foliage sprouts off with thumb and forefinger, Rhododendron, Sasanqua, Tropicals, Willow, Wisteria, Yew – pinch back soft new shoots continually, Zelkova – trim soft new growth leaving 2 leaves.
Leaf Prune:
Make certain your trees are healthy and fertilize them at least 2 weeks before leaf pruning.Apple, Beech, Birch, Elm, Ginkgo, Holly – deciduous, Hornbeam, Maples – all, Quince, Sweetgum, Zelkova.
Wire
Apple, Azalea, Bald Cypress, Beech, Birch, Boxwood, Buttonwood, Camellia, Citrus, Cherry, Cotoneaster, Crab Apple, Crape Myrtle, Elaeagnus, Elm, Fig, Ginkgo, Hackberry – after shoots harden, Hornbeam – when shoots begin to harden you can wire to shape, Jasmine – winter, Maples – all, Mountain Laurel – when shoots begin to harden, Oak, Peach, Pear, Plum, Persimmon, Podacarpus, Pomegranate, Privet, Pyracantha, Quince – Japanese, Rhododendron, Sasanqua, Sweetgum, Tamarix, Tropicals, Willow, Zelkova.
Fertilize
Apricot, Bald Cypress, Bamboo, Beech, Birch, Boxwood, Buttonwood, Camellia, Chamaecyparis – Hinoki, Cherry, Crape Myrtle, Cypress, Elm, Fig (ficus), Fir, Gardenia, Ginkgo, Hemlock, Holly, Hornbeam, Juniper, Maples, Nandina, Oak, Peach, Persimmon, Pines, Plum, Podacarpus, Pomegranate, Privet, Pyracantha, Rhododendron, Sasanqua, Spruce, Sweetgum, Tamarix, Tropicals, Willow, Wisteria, Yew, Zelkova.
Notes
This is the month to fertilize all deciduous trees except for fruiting and flowering trees. Fertilizing should be continued for all evergreen and broad leafed evergreen trees. This is a good time to start air layers of deciduous trees. It is also a good time to take softwood cuttings of current year’s growth which has hardened off. If the cutting “snaps” like a snap bean, it is mature and ready. If it bends into a semi-circle, it is still immature. The hot summer weather starts this month and it is a good idea to rotate your bonsai periodically in relation to the direction of the sun. It is also important to keep humidity at a high level around your bonsai. When watering, water benches, surrounding ground, shrubbery, etc. to increase local humidity. With good drainage, over-watering should not be a problem in the hot months of the year. However, you should be aware not to over-water. Check drainage of containers regularly. If containers stay very wet for two days ore more, take immediate remedial action by re-potting the tree in a better draining soil mixture. Junipers should be pinched continually and sprayed with a miticide for spider mite control. The trimming will develop dense foliage. Sevin can be safely used on all elms for insect control. Keep a close check on azaleas, maples, elms and zelkova for wire damage. These plants grow rapidly at this time. Continue to pinch all bonsai to stimulate compact growth. Leaf pruning of trees mentioned in the calendar will produce a new set of smaller leaves during the remainder of the growing season. If you didn’t get around to re-potting all your maples in March, you can re-pot in July after defoliating (leaf pruning) the tree. The tree must be in a healthy condition for this type of treatment. Regular fertilization once each week for the first 2 to 3 weeks in June for these trees is a must prior to leaf pruning in the last week of June. Do your re-potting in July prior to seeing color in the new leaf buds. At this “halfway” point in the growing season, you should enjoy the aesthetics of your bonsai achievements. It is a time to reflect on whether or not your goals have been met and a time to plan for future development. Best of all, it is a time for full enjoyment of viewing your bonsai.
July
Transplant / Prune
Azaleas – keep in shade for two weeks after transplanting. Buttonwood, Pyracantha, Tropicals. Elm, Hornbeam, Maples and Zelkova can be transplanted and root pruned immediately after leaf pruning provided trees are healthy and had been fertilized two weeks prior to leaf pruning.
Prune & Trim
Birch, Cedar, Cryptomeria, Pomegranate, Willow, Witch Hazel 0 after leaves have hardened.
Trim/Pinch New Growth:
Buttonwood, Bald Cypress, Cedar, Fig (ficus), Fir, Hemlock, Juniper, Maple – Trident, Pine – black, Quince – Japanese – long shoots, Podacarpus, Tropicals, Wisteria – late July – trim with scissors after blossom withers, but before new buds harden.
Leaf Prune:
Bamboo – close to the ground, Birch, Elm, Ginkgo, Holly – deciduous, Hornbeam, Maples, Privet, Quince, Willow, Zelkova. All trees should be in good health and fertilized at least two weeks before leaf-pruning.
Wire
Apple – after shoots become woody, Azalea, Birch, Boxwood, Buttonwood, Citrus, Cotoneaster, Crabapple – after new shoots become woody, Crape Myrtle – after new growth has hardened, Elaeagnus, Elm, Fig (ficus), Gardenia – as shoots become woody, Hackberry – after shoots harden, Hawthorn, Holly – new growth only – old wood too brittle, Honey Locust – late July, Hornbeam – after shoots harden, Jasmine – winter, Maple – all – after new growth has hardened, Mountain Laurel, after shoots harden, Oak, Podacarpus, Pomegranate, Privet, Pyracantha, Quince, Sasanqua, Serviceberry – after new growth becomes woody,
Sweetgum – after new growth hardens, Tamarix, Tropicals, Zelkova.
Fertilize
It is best not to fertilize this month if the weather gets too hot. However, if necessary, use a diluted water-soluble fertilizer at 1/4 of the manufacturer’s recommended label strength. The following plant material can be safely fertilized this month: Beech, Buttonwood, Crape Myrtle, Fig (ficus), Ginkgo, Rhododendron and Tropicals using a diluted fertilizer solution as above.
Notes
Be aware of the extreme heat which can damage your bonsai. Do not let your bonsai dry out, but be careful not to over-water. Rotate your bonsai periodically so that all parts of the plant are exposed to sunlight. Keep all pines and junipers in full sun for healthy growth and deep green color. Keep an eye out for insect infestations and take remedial action. Do not spray insecticide or fungicide in the hot mid-day sun. You could damage the foliage of your trees. If you must spray, do so in the early morning or late evening. This is a good month for air layering or ground layering. Trees are in vigorous growth and soil and air temperatures are very warm which should increase the success in both types of layering. You can still take cuttings of this year’s growth that has hardened off with excellent chances of success. Just be certain to keep your cutting box in the shade. Refer to the section on bonsai plant material for proper timing and medium for rooting cuttings. If you planted seeds in the spring, now would be an excellent time to transplant your seedlings into individual pots as long as they have developed true leaves. Moisture-loving plants such as Bald Cypress, Willow, Wisteria and Alders can be placed in trays or basins of water to keep their roots cool during the heat of summer and provide humidity for their leaves. Remove from trays or basins in mid-September. It is also a good time to practice sanitation around your plants by removing all dead flowers from azaleas, rhododendrons and other flower plants. This will help to prevent flower blight from over-wintering in your garden. It is advisable to use a soil insecticide this month to reduce soil insect activity. You can use either liquid Dursban or Diazinon at a rate of 1 to 2 teaspoons per gallon of water as a soil drench to control soil insects in bonsai plantings. You should repeat this soil drench just prior to over-wintering your bonsai in enclosures such as cold frames, greenhouses, unheated basements or garages.
August
Transplant / Prune
Apple, Camellia, Cherry, Cotoneaster, Holly – all, Jasmine – winter, Juniper, Mountain Laurel, Peach, Pyracantha, Quince, Rhododendron, White Pine, Yew.
Prune & Trim
Beech, Birch, Chamaecyparis – Hinoki, Cypress, Gardenia, Hawthorne, Holly – all, Hornbeam, Juniper, Mountain Laurel, Peach, Quince, White Pine, Yew, Zelkova.
Trim New Growth:
Apricot, Boxwood, Cedar, Chamaecyparis – Hinoki, Cherry, Citrus, Cypress, Juniper, Pear, Pine – black – bud pick to 2 buds every other year, Pines – strong top growth, Plum, Tamarix – trim 2/3 current growth, Willow.
Wire
Azalea – main branches and trunk only, Chamaecyparis – Hinoki, Cotoneaster, Cypress, Hemlock, Quince, Sasanqua, Yew.
Fertilize
Fertilizing the following bonsai can be beneficial to prepare for winter by using a fertilizer containing a very small amount of nitrogen such as cottonseed meal, composted cow manure or diluted fish emulsion. Single superphosphate is highly recommended at this time of year since it does not contain any nitrogen. The concept in using fertilize at this time of year is to maintain a supply of nutrients for root and trunk development without start up of top growth which would be easily damaged or killed by the onset of cold temperatures. A teaspoon of singer superphosphate for an average-size bonsai should be sufficient; 1/4 to 1/2 teaspoon for mame bonsai. Larger bonsai will require, but do be cautious. Less is better. If you are in doubt, don’t fertilize until next spring. Apple, Apricot, Azalea, Bamboo, Camellia, Cedar, Cherry, Citrus, Cotoneaster, Crabapple, Cryptomeria, Chamaecyparis – Hinoki, Cypress, Hemlock, Holly – deciduous, Juniper, Mountain Laurel, Peach, Pear, Pines, Plum, Podacarpus, Pomegranate, Privet, Pyracantha, Sasanqua, Spruce, Tamarix, Wisteria, Yew, Zelkova.
Notes
Check wiring on all deciduous trees. Wire should be removed if it is starting to cut into the bark. If wires are not removed, the branch may die over the winter. It is easier and safer for the bonsai to cut the wire off in small sections rather than trying to uncoil it from the branches and trunk. Be aware that sudden spurts of warm weather may start new growth on deciduous trees and broadleaf evergreens such as azaleas. To prevent this, keep such trees in a cool, shady area of the garden. There is always a chance for some frost this month. Semi-tropical or tropical bonsai should be gradually moved into a protected area during the first 2 weeks of this month. The cooler (40 degrees) or lower temperatures in late October could injure semi-tropical or tropical bonsai. As cooler days and nights arrive, there will be lesser demand on water by your bonsai. Be careful not to over-water your trees. In event of a freeze, do not water frozen bonsai; wait until the soil in the container thaws before watering. Strong top growth on conifers should be trimmed. On deciduous trees you can safely shorten this year’s growth slightly after all leaves have fallen. At the end of the month you should remove all fruit and seed pods to maintain strength in the trees. Berries on such trees as cotoneaster and holly can stay on until spring if the trees are in good health. You can start to collect azalea, maple and rhododendron seed this month. Maple seed can be planted outdoors this month and next month. The seed will germinate next spring without requiring stratification in a refrigerator. Be certain to mark the area where you sow the seed.
September
Transplant / Prune
Buttonwood, Cotoneaster, Pyracantha, Quince, Spruce.
Prune & Trim
Hornbeam, Pine – cork bark, Yew.
Trim/Pinch New Growth:
Buttonwood, Cedar, Hemlock, Juniper, Willow.
Wire
Azalea, Cotoneaster, Hemlock, Holly – new growth only – old wood too brittle, Jasmine – winter, Mountain Laurel, Podacarpus, Pomegranate, Privet, Quince,
Sasanqua, Yew.
Fertilize
None
Notes
Autumn starts this month. However, there could be some days as hot as in summer. This variable cool and hot weather during this month means close attention should be paid to watering, particularly to over-watering during cool spells. There is also the danger of trees re-sprouting due to early leaf drop and new growth not hardening off (maturing) before the onset of cooler temperatures. It is best to keep the soil most and cool, and, if possible, move bonsai to a shady area. If the recently styled and potted bonsai should develop long, new growth, don’t cut it off completely. A slight trimming when the new growth has hardened can be done without injury to the trees.
It is not unusual at this time of year for trunks and branches of many species of tree to swell dramatically. Check trees often during this month and October for wires that could be biting into the bark and cut them off before any damage occurs. If necessary, continue light trimming of your trees to maintain the desired outline for your bonsai style. Some trees can put out new growth this month and you should be alert to maintain your bonsai style. Check air layers which may have been started earlier. If sufficient roots have developed, cut the air layer from the parent plant and pot up. Treat these severed air layers as large cuttings and give them winter protection in a cool greenhouse.
Check any cuttings you may have made earlier an, if roots have formed, pot them into individual containers. These should also be given winter protection the first year in a cool greenhouse.
October
Transplant / Prune
Apple, Camellia, Cherry, Cotoneaster, Holly – all, Jasmine – winter, Juniper, Mountain Laurel, Peach, Pyracantha, Quince, Rhododendron, White Pine, Yew.
Prune & Trim
Beech, Birch, Chamaecyparis – Hinoki, Cypress, Gardenia, Hawthorne, Holly – all, Hornbeam, Juniper, Mountain Laurel, Peach, Quince, White Pine, Yew, Zelkova.
Trim/Pinch New Growth:
Apricot, Boxwood, Cedar, Chamaecyparis – Hinoki, Cherry, Citrus, Cypress, Juniper, Pear, Pine – black – bud pick to 2 buds every other year, Pines – strong top growth, Plum, Tamarix – trim 2/3 current growth, Willow.
Wire
Azalea – main branches and trunk only, Chamaecyparis – Hinoki, Cotoneaster, Cypress, Hemlock, Quince, Sasanqua, Yew.
Fertilize
Fertilizing the following bonsai can be beneficial over the winter by using a fertilizer containing a very small amount of nitrogen such as cottonseed meal, composted cow manure or diluted fish emulsion. Single superphosphate is highly recommended at this time of year since it does not contain any nitrogen. The concept in using fertilize at this time of year is to maintain a supply of nutrients for root and trunk development without start up of top growth which would be easily damaged or killed by the onset of cold temperatures. A teaspoon of singer superphosphate for an average-size bonsai should be sufficient; 1/4 to 1/2 teaspoon for mame bonsai. Larger bonsai will require, but do be cautious. Less is better. If you are in doubt, don’t fertilize until next spring. Apple, Apricot, Azalea, Bamboo, Camellia, Cedar, Cherry, Citrus, Cotoneaster, Crabapple, Cryptomeria, Chamaecyparis – Hinoki, Cypress, Hemlock, Holly – deciduous, Juniper, Mountain Laurel, Peach, Pear, Pines, Plum, Podacarpus, Pomegranate, Privet, Pyracantha, Sasanqua, Spruce, Tamarix, Wisteria, Yew, Zelkova.
Notes
Check wiring on all deciduous trees. Wire should be removed if it is starting to cut into the bark. If wires are not removed, the branch may die over the winter. It is easier and safer for the bonsai to cut the wire off in small sections rather than trying to uncoil it from the branches and trunk. Be aware that sudden spurts of warm weather may start new growth on deciduous trees and broadleaf evergreens such as azaleas. To prevent this, keep such trees in a cool, shady area of the garden. There is always a chance for some frost this month. Semi-tropical or tropical bonsai should be gradually moved into a protected area during the first 2 weeks of this month. The cooler (40 degrees) or lower temperatures in late October could injure semi-tropical or tropical bonsai. As cooler days and nights arrive, there will be lesser demand on water by your bonsai. Be careful not to over-water your trees. In event of a freeze, do not water frozen bonsai; wait until the soil in the container thaws before watering. Strong top growth on conifers should be trimmed. On deciduous trees you can safely shorten this year’s growth slightly after all leaves have fallen. At the end of the month you should remove all fruit and seed pods to maintain strength in the trees. Berries on such trees as cotoneaster and holly can stay on until spring if the trees are in good health. You can start to collect azalea, maple and rhododendron seed this month. Maple seed can be planted outdoors this month and next month. The seed will germinate next spring without requiring stratification in a refrigerator. Be certain to mark the area where you sow the seed.
November
Transplant / Prune
Quince.
Prune & Trim
Beech, Chamaecyparis – Hinoki, Cypress, Maple – trident, Peach, Pine – white, Quince.
Wire
Azaleas – main branches and trunks can be wired this month and the wire can remain until spring. Do not wire small branches; they may grow too quickly and suffer wire damage. Spruce
Fertilize
Using a low or 0 nitrogen fertilizer, you can fertilize the following plants before the first hard freeze and water thoroughly. At this time of year, you want to provide nutrients in the soil for root development over winter without starting up new top growth.Apple, citrus, Crabapple, Chamaecyparis – Hinoki, Hawthorn, Hemlock, Juniper, Pear, Podacarpus, Pomegranate, Pyracantha, Quince.
Notes
Be on the alert for sudden warm spells which may induce new growth. All new growth that will not have a chance to “harden off” should be removed. Remove all wires from deciduous trees to prevent damage due to sudden spring growth next year. Watch your watering carefully and do not over-water. Do not water if the soil in the containers is frozen. Wait until mid-day when the soil thaws to water. Do not allow bonsai to go into a hard freeze temperature in a dry condition. If you cannot water, provide protection against freezing. Preferably, you should water before freezing temperatures set in. All seeds and fruit, as well as leaves from deciduous trees, should be removed. You can start to collect come native material this month. If the ground is frozen, mark your selection and return on a mild day to dig it up. Do not dig trees out of frozen ground. Clean up garden area, but let fallen leaves stay on garden beds and your over-wintering bonsai. The leaves will give additional protection from frost and some of them will decompose by spring, providing humus and nutrients to the soil. Spray bonsai trees with a dormant spray to protect against over-wintering insects and fungi. Dormant oil spray is easiest to use, but be certain to read the label thoroughly and completely before using the product to avoid any damage to your trees.
December
Transplant / Prune
None
Prune & Trim
Maples, Pine – white, Spruce, Sweetgum.
Wire
Fir, Pines, Spruce.
Fertilize
Fertilizing the following bonsai can be beneficial over the winter by using a fertilizer containing a very small amount of nitrogen such as cottonseed meal, composted cow manure or diluted fish emulsion. Single superphosphate is highly recommended at this time of year since it does not contain any nitrogen. The concept in using fertilize at this time of year is to maintain a supply of nutrients for root and trunk development without start up of top growth which would be easily damaged or killed by the onset of cold temperatures. A teaspoon of singer superphosphate for an average-size bonsai should be sufficient; 1/4 to 1/2 teaspoon for mame bonsai. Larger bonsai will require, but do be cautious. Less is better. If you are in doubt, don’t fertilize until next spring. Apple, Apricot, Azalea, Bamboo, Camellia, Cedar, Cherry, Citrus, Cotoneaster, Crabapple, Cryptomeria, Chamaecyparis – Hinoki, Cypress, Hemlock, Holly – deciduous, Juniper, Mountain Laurel, Peach, Pear, Pines, Plum, Podacarpus, Pomegranate, Privet, Pyracantha, Sasanqua, Spruce, Tamarix, Wisteria, Yew, Zelkova.
Notes
This is the least active month of the year for bonsai enthusiasts. You still have to check your trees for proper soil moisture. If necessary to water, do so during the warm part of the day when the soil is not frozen.You should make certain that all conifers and other evergreen bonsai get sufficient light so their leaves maintain a high chlorophyll level for resistance to pests and disease. Do not transplant this month. You can collect native plant material this month as long as the ground is not frozen. Most deciduous and evergreen trees will be dormant this month.
Be alert to sudden weather changes. In the event of severe weather, be certain to give your bonsai added protection. Use additional mulch or place the bonsai in a cold frame until the severe weather subsides. Cold winds cause more injury than intense cold. If cold, windy days are in the forecast, you can use a simple wind-break to protect your bonsai or you can put them on the side of a structure away from the wind. You can also store your bonsai temporarily inside a garage or on a carport that does have some wind protection. If stored in a garage, remember to move your bonsai outdoors when the windy days are over. Wind protection is advised because the small branches of bonsai can be quickly dehydrated by cold winds, causing them to die and spoiling the design of the bonsai. Be on the safe side: water thoroughly on warm days if necessary and provide protection against cold winds during winter.