Satsuki Azalea Notes, May:
If you have some trees that have been touched with a frost, you will find some have only the uppermost leaves turning brown, while some have all the leaves turned brown. On those trees that have turned brown, I remove all those leaves and cut off all the terminal buds on all the branches. The auxins (growth hormones) are concentrated in the tips and by removing them it encourages back budding.
For those trees that did not suffer any frost damage, flower buds are beginning to swell and show color, You should have completed bud thinning by now, on the third year cycle trees. Some varieties begin flowering from early May onwards. On most plants, it will be found that one or two flowers become fully opened about two weeks before the main flush. Be patient. Fertilizer should be withheld from flowering plants as this will extend the flowering season. The flowers should not be misted or subjected to rain or dew after they develop color. Some form of overhead protection would be very useful. If this provides some shading and keeps the plant cool during hot weather, it will further help the quality of the display and extend the life of the flowers. The plant’s demand for water increases as the flowers develop and the soil should be kept constantly moist during this time.
Continue your fertilizing program on trees in the first and second year cycles. The first year cycle trees are allowed to grow vigorously to regain their strength. Keep up with your styling, trimming and wiring on second year cycle trees. There is an ongoing task of removing new growth buds that appear where they are not wanted. Shoots growing downward beneath the branch profiles and any growing inwards toward the trunk should be removed. Thinning and trimming of other new growth is done when the new shoots have at least four leaves. Just how hard the shoots should be cut back depends on the variety, the vigor and how it was trimmed in previous years. There is no need to be precise at this time because shoots trimmed now will bud back rapidly. The intention at this time is to mainly keep the foliage pads fairly neat and compact.
The whole purpose of this third cycle is to present a beautiful flowering display. Remove spent flowers, as making seeds only takes away energy from the tree.