WATERING – The need for water will begin to increase this month depending on the weather. However, continue to water only as needed in order to prevent root rot. Additionally, it is a good idea to water your plants early in the day so the leaves will be dry when going into the night hours thus decreasing the chance of any leave fungus.
FEEDING – As a result of longer days and warmer temperatures, plants will begin to grow again, hence the need to start your fertilizing program. There are many types of fertilizers, from synthetics to organics. Some examples are Ironite, Peters, fish emulsion, Osmocote, and Milorganite, just to name a few. Always read the application rate carefully and then cut the rate in half in order to avoid “burning” the roots of the plants with too much fertilizer.
WIRING – A good time to wire is before new leaves begin to emerge or before new growth gets too thick to see the branches. Furthermore, new growth can easily get in the way during the wire process and be broken off, consequently making the job more frustrating. Continue to inspect the wire on all your trees to see if it’s time to remove them. Leaving the wire on the plant for too long will disfigure the branches; therefore, remove the wire if the branch remains in the desired position or if the wire is cutting into the cambium.
PESTS AND DISEASES – The activity of insects and diseases will begin to increase this month as temperatures rise. Therefore, keep a close eye on your collection and look for anything unusual such as curly, stunted new growth; blotchy or spotted, white or pale yellow areas on the leaves; white, cottony patches; spots of brown on the leaves; and insect excrement. Use environmentally friendly treatments such as the encouragement of beneficial insects, hand picking larger harmful insects, and/or the use of soaps and oils. Always remember to spray a small branch first in order to make sure there will be no phytotoxic* reaction to the plant from the soap and oil spray. An example of a plant that will drop all of its leaves if sprayed with soaps and oils is Fukien Tea.
TRIMMING – This is wonderful time of the year for your collection because the plants will begin to put out delicate, lush growth. However, this will also signal the beginning of another season of constant, but important trimming. After allowing the new growth to produce about four to six leaves cut it back to about two or three leaves. The result of continually trimming your tree will be twiggy branches thus producing a more refined bonsai.
PRUNING – The old saying “timing is everything” is quite applicable during spring. Temperatures are beginning to warm up and the danger of frost and freezes are over, hence this is an excellent time for heavy pruning. The removal of large branches will encourage new, tender growth in conjunction with fresh, spring vegetation. Additionally, wounds heal faster when the tree is actively growing because the plant is manufacturing more food and producing cambium at a faster rate.
LIGHT – Sunlight will continue not to be too severe this month. For that reason, keep giving all your plants as much sun as possible including less tolerant ones such as maples and azalea plants. Maintain rotating your trees on a weekly basis, thus preventing them from becoming one sided.
TEMPERATURES – The colder temperatures will most likely discontinue this month and will be replaced by milder, less fluctuating extremes. As a result, it will not be necessary to bring in your tropicals. However, I remember one year when the coldest night of the entire winter fell on March the first! Remember, the last day of winter is not until March 20th.
REPOTTING – If you have not finished repotting your evergreens, quickly continue to do so. On the other hand, avoid repotting your deciduous trees if they have begun to put on new growth because there will be a greater chance that they will go into shock and die if repotted. It may be better to wait till next winter if deciduous trees are growing. If you keep maintenance records on your plants, refer to your notes to see when the last time a particular plant was repotted. Avoid repotting all tropical plants.
COLLECTING MATERIAL – Hopefully, you have already dug up any landscape material that have the potential to make a good bonsai plant. Keep it in the shade and mist daily until you begin to see new growth. Slowly acclimate it back into a full sun location. Allow the new growth to grow untrimmed in order to allow the plant to build up food reserves.