Volume XVII, Issue 38 # September 17 - September 23, 2009

The Bay Gardener

by Dr. Frank Gouin

What Do Azaleas and Blueberries Have in Common?

Both are acid-lovers, so now’s the time for transplanting

Most acid-loving plants, like azaleas, rhododendrons, mountain laurel, andromeda and blueberries, transplant best through September. Transplant now, and you’ll get almost normal growth next spring.

This is the time of year when these species cease vegetative growth for the season and resume root growth. Most woody plants do not grow new roots at the same time that they are producing new shoots and stems. Most acid-loving plants stop producing new top growth to initiate flower buds for the coming spring. As soon as the stems stop growing, the roots resume growth. Thus by digging and transplanting these species now, you are allowing the plants to become well established prior to winter, when all growth will cease.

When the plant is growing new leaves and stems, the roots are supplying these new leaves and stems with water and nutrients. When the roots are growing, the leaves are providing the roots with sugars and other substances manufactured from photosynthesis.

Azaleas, rhododendrons, blueberries, mountain laurel and other acid-lovers are very shallow-rooted plants. This means that the uppermost roots should not be covered with more than one inch of soil. To assure good survival and lush growth next spring, make certain that the soil in which you are transplanting contains a minimum of five percent organic matter and has a pH not to exceed 5.5. This means having your soil tested ASAP so that you can make the necessary adjustments at the time of transplanting. Trying to correct soil problems after the plants are in the ground is very difficult.

Transplant to soil that is well drained. Azaleas, rhododendrons, blueberries and mountain laurel will not grow well in poorly drained soils.

When Leaves Fall, Make Compost

Q I agree that compost is the most beneficial addition to a flower or vegetable garden. However, I recall you said that about three bushels of leaves when composted equal about one cup of usable compost. Based on that ratio, the average homeowner without farm acreage would never get enough usable compost except for the smallest of gardens. And when I have leaves in the fall, I don’t have enough green matter to add to the mix. Doesn’t commercial fertilizer still have to be the primary nutrient?

–Michael Brownstein, via email

A One bushel of leaves will make about one cup of compost. In autumn, drench the leaves in your compost pile with a slurry of mud containing about one cup of urea with five gallons of muddy water per four to six bushels of leaves. The mud will not only help wet the leaves but also provide the microorganisms necessary to decompose the leaves with the help of the nitrogen from urea.


Ask Dr. Gouin your questions at frgouin@erols.com. All questions will appear in Bay Weekly.
Please include your name and address.