What to do this month - Waverley Bonsai Group

January

Check wires on all trees regularly as trunks and branches expand/grow rapidly at this time of year. As new branches harden you may start to apply wire. Pinch back new growth on shoots as early shoots start to grow and elongate. More frequent pinching and nipping will promote the development of fine branches and thicker foliage pads. Maples grow rapidly and put out long shoots, Pinch back to first pair of leaves. Remove shoots with long internodes. As azaleas finish flowering, prune back to maintain shape of the tree. Repot after flowering. Do repotting of natives in January and February. With the warmer weather here ensure your plants are obtaining sufficient water…remember to water thoroughly and regularly. Regularly check plants for pests and diseases. You can defoliate now, if you haven’t already done so. Sit back and enjoy your trees whilst sipping on your favourite beverage. Remember that deciduous plants come from cooler climate area and therefore may need shelter from the hot burning rays of the summer sun. Reduce fertilizing during January and February For pines, allow the soil to dry out between watering as this reduces the size of the pine needles. Use mesh over your moss to keep the blackbirds away and to go eating elsewhere. To keep mosquito larvae from growing on your water trays, put a layer of sand in the bottom.

Febraury

Keep checking wires on all trees regularly as trunks and branches expand/grow rapidly at this time of year. Pinch and nip new growth on shoots to promote the development of fine branches and thicker foliage pads. Maples grow rapidly and put out long shoots – pinch back to first pair of leaves. Remove shoots with long internodes. When leaves have hardened and plants are strong, you can defoliate, if required, to reduce the size of leaves on your plants. Repotting of natives, should be completed in February. Figs and cedars should be repotted by late February With the warmer weather here ensure your plants are obtaining sufficient water…remember to water thoroughly and regularly. Be vigilant for signs of leaf end browning and burning. Never put water on leaves in hot sun. Pests and diseases need to be looked at closely. Look under leaves and branches too. Reduce or even eliminate fertilizing during January and February For pines, allow the soil to dry out between watering as this reduces the size of the pine needles. Kill star weed and liverwort with brown vinegar (apply with cotton bud or a fine paint brush).

March

Check wires on all trees regularly as trunks and branches expand/grow rapidly at this time of year.

Fertilizer: The best time to fertilize your bonsai is from early spring to late summer. Look for a fertilizer that has a low Nitrogen content to feed to your tree year-round. Use a tomato plant fertilizer as it has the correct blend of ingredients to thicken and harden trunks and improve fruit and berries on trees.

Pruning: Summer pruning is important. Prune for size control. Head back the new growth that has exceeded your preferred shape or size.
Apples and pears, pip fruit, should be summer pruned to encourage the production of fruit spurs, carrying flower buds. Pinch back new growth on shoots as early shoots start to grow and elongate. More frequent pinching and nipping will promote the development of fine branches and thicker foliage pads.
Maples grow rapidly and put out long shoots. Pinch back to first pair of leaves. Remove shoots with long internodes.
Repotting of natives should be completed by now.

Water: With the warmer weather here ensure your plants are obtaining sufficient water…remember to water thoroughly and regularly. Remember that deciduous trees come from cooler climate areas and therefore will need shelter from the hot burning rays of the summer sun.
For pines, allow the soil to dry out between watering as this reduces the size of the pine needles.

Pests & Diseases: Regularly check plants for pests and diseases.

Propagation: Get ready for cuttings of semi-hard wood in Autumn when the tree vitality is good. Use the pruning off-cuts – up to 100mm max in length to let the roots form in a propagating mix and good sheltered cover.

April

Fertilisers: As Summer ends and Autumn starts, lower the Nitrogen content in the fertilisers. Tomato plant fertilisers have the correct blend of ingredients to thicken and harden trunks and improve fruit and berries on trees, or use a fertilizer with lower N, but higher P & K. Remember to water thoroughly.

Pests & Diseases: Regularly check plants for pests and diseases. Aphids love the young Camellia and Maple leaves. Kill star weed and liverwort with brown vinegar (apply with cotton bud or a fine paint brush).

Planting in the Ground: Start to prepare a garden bed, in readiness for when you can plant some of your trees in the ground in a few months time.

Autumn Colour: You should be starting to enjoy some touches of autumn colour, colourful berries and small fruit on your trees. If you don’t have any of these trees in your collection, it is a good time to scout around the nurseries and buy one.

House Keeping: Remove dead needles on your pines, clean them up generally and cut off any dead wood, this allows more light and air to circulate around your tree.
Inspiration Attend the coming bonsai shows to seek more inspiration.

Cuttings: As for last month, the semi-hard wood cuttings are done in Autumn when the tree vitality is good. Use the pruning off cuts – up to 100mm max in length to let the roots form in a propagating mix and good sheltered cover. Plant them quickly or in water if there’s a delay involved.

May

Pests & Diseases: Keep checking plants for pests and diseases.
Avoid Pruning deciduous trees because growth spurts can get winter burns when / if frost comes. Start to remove any fruit and berries to allow your tree to recover.

Conifers: Last growth on some conifers like Junipers and Cryptomerias means one last pinching can be done before winter sets in.

Wires: Remove wires and let trees rest over winter.

House Keeping: Constantly remove all fallen leaves from your benches and pots. As well as keeping the area tidy and clean, it removes a potential source and habitat for pests and diseases. Scrub down the benches to remove algae and dirt build-ups and disinfect discarded posts.

June

It’s the start of Root Rot Season!
Remember to reduce watering except when we have a prolonged dry spell. If the soil in your bonsai pot is constantly wet during winter, root rot may occur – look for signs of leaf dieback and white rings on the roots at soils level.

Pests & Diseases: Regularly check plants for pests and diseases.

Maintenance: Remove any fruit and berries to allow your tree to recover.

Shape Your Tree: This is a great time of the year to shape your trees. All the leaves have fallen off your deciduous trees and you now have the skeletal framework enabling you to see where last season’s excess growth has spoilt the tree’s shape or design. Firstly, cut off any dead wood, then re-shape or restyle.

Fertilizing: Fertilizing isn’t required for any dormant trees.

House Keeping: Constantly remove all fallen leaves from your benches and pots. As well as keeping the area tidy and clean, it removes a potential source and habitat for pests and diseases.

Visuals: You may still be enjoying some touches of autumn leaf colour, colourful berries and small fruit on your trees.

July

Shape & Redesign: Autumn to winter is an excellent time to shape, re-style and re-design any of your trees, especially with deciduous trees. The bare branches allow you to see your tree’s framework and any defects.

The Visuals: Good time to go rock collecting. Spend time making your display area more attractive; re-position your trees and/or build or repair shelves.

Tree Health: Move trees into sunnier positions as required. Reduce watering and only water in the mornings AS NEEDED as this reduces the likelihood of root rot. Also allow soil to dry out between watering. Remove excessive moss to improve air circulation and drainage. Retain excess moss in a seed tray for later use.

Records: Excellent time to update your records.

Think Ahead: Prepare or obtain your soil in preparation for the potting up season. Obtain pots that you will require for when you pot your plants into bonsai pots.

Maintenance: Clear away dead leaves and debris from your pots and regularly check trees for fungus and insect attack.

Frost Protection: Move trees that require protection from frost and cold to more sheltered areas.

August

This is a busy time of the bonsai year, as trees are root pruned and re-potted before the buds burst.
Prepare for potting by sorting your pots; ensure they are clean, choose which pots to use for which trees.

Best Times to Re-pot: For deciduous trees, the ideal time for re-potting is when the leaf buds start swelling but are not yet opened into new leaves. Maples develop new growth very quickly. Mulberries and Liquidambers are usually very early in sending out new shoots; Zelkovas and Beeches later.
Cedars, spruces and pines tend to be early; Cryptomerias later.
Most blossoming and fruiting trees are best potted after flowering, but sometimes leaves emerge during the flowering period – repot before leaves emerge, even if during flowering. Use the swelling of new buds as a guide to ideal potting times.

Some variations: Cotoneaster late spring to summer. Flowering Quince best in autumn.

Other Trees:

Chinese Elm may be root pruned later
Figs late spring (October to February)
Azalea spring, after flowering
Eucalypts summer
Serissa later in spring
Juniper anytime

Plants that have been re-potted should not be fertilized for about 4-6 weeks and I usually place the plant in a sheltered area for most of that period of time.

Root Pruning: Most deciduous trees can withstand quite drastic cutting of roots and even bare-rooting.

Warning: Beech, Hornbeam, Oak and Conifers should not be bare-rooted as they have mycorrhiza (a beneficial fungi) on their root systems.
Trees are generally top-pruned in conjunction with root pruning.

When to Fertilize: Do not fertilise directly after root pruning and potting trees, as this may burn roots. Start fertilising these trees once they have recovered from the re-potting and are growing strongly again. This can vary from a month after re-potting or until late summer.
Trees that have not been root pruned can be fertilized with a weak solution as soon as new buds burst and leaves begin to unfold.
Wait a Bit to Wire
After re-potting, wait a few weeks before attempting to wire a tree, to avoid damaging fine roots just emerging. Do not wire new shoots until the wood begins to harden.

Watering: Deciduous trees may need more water as they come into new growth, so adjust watering. Water thoroughly but do not over water.

September

Re-potting & Pruning: The last of the trees should be root pruned and re potted before the buds burst. Trees are generally top-pruned in conjunction with root pruning.

After Re-potting: Wait a few weeks before attempting to wire a tree, to avoid damaging fine shoots just emerging. Do not wire new shoots until the wood begins to harden.
Plants that have been re-potted should not be fertilized for about 4- 6 weeks.
Place the plant in a sheltered area for most of that period of time.
Maples develop new growth very quickly.

Blossoming & Fruiting Trees: Most blossoming and fruiting trees are best re-potted after flowering, but sometimes leaves emerge during the flowering period – re-pot these before then, even if during flowering.

Fertilising: Start fertilising trees once they have recovered from the re-potting and are growing strongly again. This can vary from a month after re-potting till late summer.

Conifers: Shape conifers and deciduous trees as long as growth is not apparent. Add wiring to set the shape but monitor for any signs of cutting in as the growing season proceeds.

October

Changeable Weather: Check the trees daily when possible as this is still a time for changeable weather.
Watch for the growth spurts that might need a bit more water.
Leafy trees take more water but go lightly on fruiting trees.
Carefully look at the wire and test to see if it is biting in.
Remove the wire if the branch has set, otherwise rewire it in a different place and loosen the pitch.

Repotting: When the buds are growing out, it is too late to do repotting.
In any case, finish all repotting before November.

Feeding: October is the time for a 2nd feed but don’t do feeding until the buds are growing well.

Pruning & Shaping: Maples grow rapidly and put out long shoots. Pinch back to first pair of leaves. Remove shoots with long internodes.
You can do pruning but make sure you seal the cuts.
Conifers can still be shaped. This is a good time for conifers and they will like a position that gets sunshine. For air layered conifers, this is the time to cut off last year’s work and replant the new section. Nice tender leaves attract the pests, particularly aphids. Conifers can exhibit problems that need insecticide applied and again 2 weeks later.
Scrub trees to get rid of old algae and scaled bark.

November

Check Your Wires: Check wires on all trees regularly as trunks and branches expand/ grow rapidly at this time of year. As new branches harden you may start to apply wire.
For those who work on the trident maples and the corky bark elms – keep an eye on the wire. The heavier lower branches and the apex will thicken the most quickly and start to bite in. Let the wire cut in a bit and then cut it off. Then shorten those branches and that will allow the thinner branches to catch up and then do the same to those branches once they thicken.

Pinch Back New Growth: Pinch back new growth on shoots as early shoots start to grow and elongate. More frequent pinching and nipping will promote the development of fine branches and thicker foliage pads. Maples still grow rapidly and put out long shoots. Pinch back to first pair of leaves. Remove shoots with long internodes.

Air Layering: This is the start of air layering season, so select next year’s starter tree from the limbs of another and in a few weeks to a couple of months they will be ready on most species.

Azaleas: As azaleas finish flowering, prune back to maintain shape of the tree. Repot after flowering.

Repotting: Junipers and cedars can be repotted now.
Azaleas repot after flowering.

Natives: Leave repotting until November/ December or even wait until early next year.

Fertilize: Fertilize regularly using liquid fertilizer in conjunction with organic fertilizer.

Watering: With the warmer weather here ensure your plants are obtaining sufficient water. Do not leave your plants on concrete or brick paving (they get too hot).

Pests & Diseases: If you see ‘slug trails’ on leaves, get out the spray and get the aphids under the leaves above. Ants are a tell-tale too as they feed off aphids.

December

Check wires on all trees regularly as trunks and branches expand/grow rapidly at this time of year. As new branches harden you may start to apply wire.
Pinch back new growth on shoots as early shoots start to grow and elongate. More frequent pinching and nipping will promote the development of fine branches and thicker foliage pads. Maples grow rapidly and put out long shoots. Pinch back to first pair of leaves. Remove shoots with long internodes.
Azaleas when the late flowering has finished, prune back to maintain shape of the tree. Repot shortly after flowering.
Cryptomerias are OK to prune into shape in the November – March period. Trim out the vertical shoots and keep the crown trimmed to invigorate the lower branches. Drooping ends can be wired to shape and dense growth needs to be trimmed out to keep insects away. Pinching the shoots when they are still young is the main task over summer. Fertilise from Nov-January.
Young Zelkovas and Elms can be pruned in December. Mature ones are defoliated. Fertilize regularly using liquid fertilizer in conjunction with organic fertilizer.
Natives Leave repotting of natives until January/ February. Ensure your plants are obtaining sufficient water. Put water trays under the trees to keep the moisture and humidity moderated. If you are worried about trays filling and over-watering, drape a wick of cloth or tying-stocking out of the pot and let it siphon out (to a tree below?). Regularly check plants for pests and diseases.
Heat!! Do not leave your plants on brick paving or tin shed roofs (they get too hot).