SEASONAL SUGGESTIONS
No. 72 - November/December- 2001

WINTER CARE- IMPROVING FORM AND HEALTH

By Marty Mann

Each year is like a running clock. Spring is the time of sunrise and reopening. Summer is the growing time for the development of new growth and form. Fall is the late, cooler months with the transformation of colors and changes as the hours of dusk approach. And now, the late evening fades to the dormant winter season. Quiet time arrives, for it is nightfall.

As we speak of our trees (not the frantic pace of holiday time) it is the time of year, dusk and nightfall, when the ways of nature become our guide as to what must be done. The activities of this period come from our own experience, from what we have read, and from the teachings of our sensei. It’s a period of transformation in the mind's eye.  A chance to study each tree--without concern for constantly changing growth. It’s a time to discontinue the feeding care and reduce the watering needs, to devote time to designs and plans for the beginning of next year. The clock runs on.

Enhance the beauty of winter silhouettes by the selective pruning of crossing branches and heavy top growth. Trim the overgrown whips that have developed during the past growing season. Now is the time to create relative size and shape of new growth to maintain tree design. Allow the waning winter light to penetrate into the heart of the tree to encourage new buds and new growth in the spring. This is the time to remove the trash of falling leaves to eliminate the winter harbors of insects and fungus. Continue a program of regular insecticide and fungicide spraying on the dry days between (hopefully) intermittent winter rains.

Keep the foliage misted.  Preserving the health of a tree involves proper watering procedures during the dormant period in the cooler weather. Deciduous trees have transformed from the beautiful fall colors, to barren silhouettes. Evergreen trees appear dull, inactive and unchanging. Since warm weather does occur at this time of year, potted trees must be watered regularly, but cautiously, even if brief winter rains happen. Coolness brings slow growth and during this period of dormancy, your trees require only a dampening of the root zone since transpiration of moisture is essentially non-existent. Watch out for the prevailing and drying winds. The porosity of a good bonsai soil mix allows moisture to quickly escape a shallow pot. If you count on the regularity of an automatic timed watering system, the timing cycle should be adjusted for winter requirements.

Insect and fungus control during dormancy is as important as in spring and the active repro­ductive time of summer. November usually brings cooler days. This is an ideal time to protect bonsai from the over wintering of fungus spores and insect larvae. Use a dormant spray such as ORTHORIX (lime sulphur) as a fungicide. As a precaution, avoid root damage by covering the surface of the pot with plastic to prevent run-off or drip of the spray. A light mist of lime sulphur on the top and bottom of the foliage and woody surfaces is effective. Avoid spraying azaleas, camellias and other acid loving plants. Do not spray any buds that show color due to unseasonable warm weather. Other excellent dormant sprays are BORDEAUX OIL or VOLKE OIL. Insects are relatively inactive during cooler months. It’s a good practice to apply a mist of DIAZINON or MALATHION each month for aphid control and spider mites, and SEVIN for ants in order to catch any newcomers or left over insects. Apply a light spray around the growing or display benches.

Fertilization is generally ignored during dormant months. If you practiced a low nitrogen feeding program since late summer or early fall, trees entered this period in reasonably good health. It is common, in the warmer California climate, to continue some fertilization on evergreen and conifer material. The woody portions of trees continue to add growth to the trunk, branches and roots. Partial dormancy requires some nourishment. A light feeding of cottonseed meal (70%) and bone meal (30%) is best. A 0/10/10 formula also supplies the necessary phosphorus, potassium and slight trace elements of other minerals that maintain good health and color. Deciduous trees normally should not be fed during the dormant pe­riod. Confine feeding to soil surfaces since foliar feeding encourages green growth that can be damaged by unexpected periods of cold weather.

Protect the roots of established bonsai from root rot. Trees will show signs of root problems by leaf discoloration and premature drop. Small branches will shrivel. Check the rootage—healthy roots show colors ranging from white to brown. Sick or dead roots will be black or soft. Solutions for this problem range from immediate repotting to a well-drained soil or planting media to the applications of specialty fungicides that attracts root fungus. Don’t let the plant just die!

November and December are good moths to review the placement of branches. Apply wire before the branches begin to swell with early spring growth. Dormancy time suggest less sap in the branches—making them more brittle. Be careful to use wire that is somewhat stiffer than the branch that requires placement.

Clean up around the bonsai areas. Don’t allow litter and leaf drop to accumulate. This material creates a haven for insect eggs and fungus spores to thrive. All leaves, seed pods and dried flower heads may now be removed from potted material. Particularly, check the pine trees. Remove any disfigured or long needles that show brown tips.

Winter moss that may be forming in the shaded areas around the yard can be gathered and placed in flats. Let it grow for use in the spring to dress your bonsai. It’s advisable to remove any build-up of moss that has accumulated as a thatch on potted material. This build-up tends to reject surface watering and prevents moisture from penetrating to the roots.

Reconsider the arrangement of trees on your benches. Those that may have been moved into shaded areas to avoid hot summer sun can now be exposed to better light. This is an excellent time to sort out trees into first-things-first categories. Attend to the trees that require winter trimming while the branch silhouettes are easy to study. Early in spring, repot the trees that show signs of being root bound. Check the rootage on all trees. Allow some surface exposure to encourage a change from soft surface tissue to the adaptation of texture similar to the outer trunk bark.

Prepare a spring inventory of potting soil mix, screening materials, and aggregates such as pumice, sand, lava rock, D. G. etc. Store a supply of humus such as fir bark, redwood bark, or peat moss to amend the basic soil mix.

Take care of the bonsai tools. Winter rain and general high humidity encourages rust. Clean and sharpen tools and apply a good rust inhibiting oil finish. Remove the build up of sap and grime.  Clean up the accumulated old pots that you may need during the repotting season in spring.

Perhaps a bit premature but—Life’s precious moments don’t have value unless they are shared. Life is a journey—not a destination. Have a happy, healthy new year.