We are now entering early summer and your trees should be in full leaf and enjoying the warmer weather and long hours of daylight. Here is a quick generic guide to bonsai in June but for individual species you may need to adjust the guidance as well as for the developmental stage your bonsai trees are at.
Continue to check your trees daily and water as required and you will have noticed they will be starting to take up more water and dry out quicker. This is now the time to really increase your watering with the leaves fully out and hardened off. Water in the mornings ideally and if necessary water more than once a day.
None required unless emergency repotting required where the pot is damaged or there is a pest concern or drainage issue. Try not to damage the roots during an emergency repot and just place the tree in another pot of the same size or larger for the time being until the correct repotting season without root pruning or disturbance.
This is the time to start feeding much more regularly and heavily while the trees are actively growing.
Organic feeds are preferable to chemical feeds including products like liquid seaweed and this can be fed daily as part of the watering regime or less often depending on the stage of development of the tree.
Ideal feeding at this time is liquid feed as the watering regime has picked up and you can feed with each watering, and the general rule is little and often.
This is the time to prune back all excessive growth on deciduous trees and start to work on removing the larger leaves on a regular basis in preference of retaining the smaller leaves forming after the larger leaves have been removed.
It is also a good time to carry out a full or partial defoliation of broadleaved trees but only if the tree is healthy enough. Ensure that if you do a full defoliation that you place the tree in a more shaded position rather than in full sun following a full defoliation.
Now that the leaves are present continue to maintain the shape through regular trimming and remove the terminal shoot in some species to aid with creating a more compact form.
Continue to prune tropical trees to maintain their shape and trim the new shoots.
Leaf cutting is also applicable for some species like maples but ensure that they are vigorous and healthy before you carry out leaf cutting and it may be more suitable to do a section of % at anyone time.
This is not applicable at present unless any trees are being repotted but for the majority of species they should already have been done.
Insects and pests
Check for the newly emerging bugs and pests like green and black fly, red spider mite, scale insect, mealy bug as well as vine weevil beetles. With the onset of warmer weather insect pests can start to emerge and are more likely to appear on the new shoots and leaves.
Watch out for the on set of mildew and prune out any damaged leaves or treat any infestations if found. Spray with insecticide as required or once a month for pest prevention using products like SB Invigorator. Methylated spirits cotton buds are an effective method of removing scale insects from branches.
Moss and weed control
Continue to keep this in check and treat or remove unwanted moss and remove any newly forming weeds.
Wiring can be started on some of the larger branches if the tree has been defoliated but otherwise it is not a good time to wire as the process can damage the foliage.
Winter and frost protection should no longer be required but shade and wind protection may be necessary to avoid leaf scorch or wind burn of the new leaves.
Continue to update your bonsai records and photograph your trees to record their progress.
This is something everyone should do each time they use their tools but often it is not easy to do depending on how often you are using your tools. However, it is good practice to clean and sharpen your tools after use and this is a good time to go through your tool kits and clean them up before the start of the pruning season.
If you have trees out in display areas check that they are not drying out or getting too much sun and ensure they have shade if required as the temperatures during the day currently are fairly hot.
Also check for wind protection and stability of trees