Bonsai Reference - Summer Care

Hold off any activity on the soft deciduous growth until it hardens. Keep your eye on the upper por-tion of these fast growing trees. Branches tend to thicken and ruin the taper of the design. Heavy top growth also deprives the bottom branches of light and nourishment. Watch the wires you put on since damage occurs quickly when growth is active. Remove the fast growing water shoots that come out of the root system or the lower trunk area. Cut back on the long internodes and opposite branches. Don't allow the upper branches to take over and shade the lower areas.

Leaf pruning may be done later in June or early July. Be sure the trees are healthy and growing vigor-ously. Feed them well two weeks before you proceed. It is often better to leaf prune only partially. Start with oversized leaves, damaged leaves, or selected areas of the tree. This piecemeal approach will reduce the shock to the tree. It is also best to leaf prune a tree in alternate years. The new leaf growth will return, slightly smaller, with a fresh springlike color and beauty. Better fall color will also be your reward. Watch the hot summer breezes since new growth can be easily harmed. If you leaf prune almost all of the foliage you must treat the tree as you would during dormancy. Reduce the water and do not feed until new growth appears.

June is also a time for soft woods to harden. Cuttings can be taken and developed. Air layers, for propagating new bonsai will do well now. This is an active growing period, and new roots will develop sooner with moist, warm conditions.

Feeding is an ongoing responsibility. Periods of fast growth are also periods of great need. Continue feeding during May and June; however, as the summer approaches, you must slow down this new growth by reducing the percentage of Nitrogen in your formula. To promote the best fall colors, change to fertilizers with larger proportions of Phosphorus (P) and Potash (K). Keep in mind that Nitrogen (N) will create green color so be sure your selection still has some of it. The addition of some Aluminum Sulfate on the surface of a plant will increase acidity for acid loving plants.

Taking care also means protection. As the weather improves it encourages the growth of the undesir-able population of aphids, green flies, spider mites, white flies, and scale. If Junipers appear to be yellowing or looking sickly - suspect spider mites. In Pines, if there is evidence of a white woolly substance in the interior of the tree - suspect borers. Insects suck plant juices and cause considerable damage. Mites are quite small and can be easily discovered by shaking a branch over a white surface and watching the tiny red spots move. Use a few drops of Volck oil in your insecticide sprays to improve effectiveness. Be attentive to regular application of insecticides and mitecides. Apply Malathion®, Sevin®, Isotex® for insects.

Warm weather will also increase the productivity of various fungus infections. Use Captan®, Beno-late®, or other general purpose fungicides to avoid damage from mildew and leaf spot. A drop or two of a mild soap solution or other wetting agents in your formula will improve effectiveness. The soap will emulsify the oils in chemical sprays and cover the leaf and bark surfaces. This will smother and kill many chewing, flying and sucking insects more effectively. Watering, another ongoing activity, must be suited to each tree in your collection. Each tree is indi-vidual and often requires a distinctly different treatment. Location on your bench, and exposure to varied spans of sunshine will affect the drying time and the expiration of moisture. Soil mix will also affect the drainage and the drying time. Water your trees early in the morning or late in the day, or both, if it's hot. Keep water off of the leaves during hot weather or while exposed to afternoon sun to avoid leaf damage. Remember, watering properly is a skill acquired with years of knowing what your trees like and how they best react with good health and color. Your best measure of correct watering is to allow each pot to drain through the bottom holes and water when you see signs of drying out.