Cape Cod Bonsai Club

The design of your bonsai is only half of the objective. Keeping it alive is where horticultural science is critical. Each month at our meetings this report is given to our member to help them anticipate issues and opportunities for the coming month and season. Our present report comes from long time member Carol Ebreo. She has been a member of the club for over ten years. Our past reports have come from Mark Heinlein, Mike Novik, and Ray Perry.

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There are a few tasks that cannot be neglected this month, the most important of these is watering. On hot days trees will have to be watered more than once, shohin (small trees) up to 4-5 waterings daily, and medium sizes perhaps two. You can decrease the need for multiple waterings by putting trees in mid-day shade, placing small trees in water trays, or playing them on trays of moist sand. Remember that pines like to go a bit dry between waterings. Defoliated trees do not need as much water as usual until their new leaves appear.

Flushing the foliage with water will also discourage spider mites. You can encourage their departure by using topical insecticides as well. These will also remove aphids. Check trunks for borers as they can usually be found by the "frass" near their entry point. Check under your pots as well for worms, slugs, sow bugs, and earwigs that enter drainage holes and chew on roots. Granular insecticides will send them scurrying.

Additional pruning may still be necessary as some trees are still in vigorous growth, but during hot mid-summer weeks we can cut back on or even suspend fertilizing. High soil temperatures cause roots to become inactive and excess fertilizer can cause a buildup of soluble salts.

Pay attention to any wires on your trees, as a few days neglect can cause scarring that may take years to heal over.

Softwood cuttings can still be struck and most will root readily. Jin and shari can be recoated with lime-sulphur now, which will prevent mildew on the deadwood.

This report was done by Ray Perry (edited by Andy Arnault). Reprinted from the CCBC Horticultural Almanac 

 Horticultural Report