Regional Gardening Reports :: National Gardening Association

Northern California Coastal & Inland Valleys

May, 2007
Regional Report

Care for Wild Oaks

If you have old wild oak trees on your property, it's important not to raise or lower the soil grade between the trunk and the drip line. Never water within 4 inches of the trunk or allow water to stand in the area under the canopy of leaves. Keep old trees groomed by removing dead limbs and branches. Remember, no irrigation during the summer for mature oaks.

Fertilize Cymbidium Orchids

Make the fertilizer switch on your cymbidium orchids now. We are blessed with the ideal climate for these exotic that are native to the mountains of Asia. To promote the best bloom, plants need a low-nitrogen fertilizer such as 6-30-30 or 6-25-25 until the buds set. Apply the fertilizer half strength every week until the end of the year. It's best if the potting bark is damp before fertilizing.

Keep Ivy Out of Trees

If ivy is growing near the base of trees, keep it on the ground where it belongs and do not allow it to climb up the trunk. As the tree grows and expands in girth, the stems of the ivy also expand, eventually killing the tree by strangulation. Cut or pull any ivy out of trees and prevent future invasions by constant vigilance.

Plant Tuberous Begonias

Amend a shady garden bed with oak leaf compost to a depth of 8 inches. Water well and set tuberous begonias, concave side up, up to their shoulders in the prepared soil. Protect from snails and slugs until new growth reaches 4 inches. At that time, begin fertilizing every other week with half strength 22-14-14 to promote leafy top growth. In four weeks, switch to 15-30-15 to promote bud development. Tuberous begonias don't need nearly as much water as you would imagine -- once a week is more than enough. Apply water to the base of the plant near the tuber and never on the foliage to prevent powdery mildew.

Fertilize Shade-Loving Plants

Shade-loving plants such as columbines, hostas, coleus, and impatiens don't use water as quickly as plants grown in full sun. They also don't use fertilizer at the same rate. A good way to fertilize plants growing in the shade is to use a slow-release fertilizer applied directly into the soil surrounding the plant. The fertilizer will slowly dissolve whenever the plants are watered -- for up to three months.


Today's site banner is by EscondidoCal and is called "Water Hibiscus"