The Bay Gardener
By Dr. Frank Gouin
Fountains of Gold for Spring ’07
Prune forsythia now
When the last petals of forsythia have fallen, it is time to prune. Forsythia’s beauty is spoiled when plants are sheared or left unpruned. When either sheared repeatedly or left un-pruned, forsythia plants produce fewer and fewer flowers each year and eventually die out. A properly pruned forsythia should appear like a yellow fountain of flowers born on slender brownish-yellow stems.
The proper pruning of forsythia requires that you get down on your knees and remove all old branches that have gray bark. If you have not pruned your forsythia properly, this could means cutting all of the branches as close to the ground as possible. If you prune now, new vigorous stems will emerge from the roots within a few weeks. Allow these stems to grow without further pruning all summer long. If the plants are in good condition, the new stems will grow to a height of five to six feet by mid July and their bark will be brownish-yellow in color.
If your forsythia are relatively young, you need only remove the old gray bark stems near the ground and allow only the lighter brownish-yellow colored stems to remain. Prune all stems smaller than a pencil-width in diameter and remove all stems bending sharply toward the ground. You do not want these stems to touch the ground, because they will take root and produce new plants, which can result in overcrowding. When you are done pruning, all that should remain are upright single stems with brownish-yellow bark.
By properly pruning your forsythia now, you will be guaranteeing a profusion of flowers on your plants next spring.
Q I have been trying for five years to plant Ilex Crenatas under my windows. I have an above-ground, split entry with a very large overhang. I have moved the holly out farther, but now my oak trees are choking the roots. I would like some four-foot-and-under shrubs to anchor the house but cannot get too close due to the overhang. All areas are shady, and I live close to the river in Cape Arthur. Soil is acceptable. I have many hostas and gumbo azaleas. The gumbos are also not thriving, I think due to the roots of trees. We have a very wooded lot and of course lots of shade. Any recommendations for shrubs that will thrive in shade, with competing roots?
Any recommendations for ground cover and perennials for these conditions? I do not do too well with annuals: I do not know why.
Karen Piccoli, Severna Park
A For a good groundcover, try liriope. For a shrub, try acuba. Both are very shade tolerant, and their roots will compete with tree roots. However, you do need to irrigate them well until they become well established.
Start Your Easter Amaryllis Now
Q Isn’t there something I’m supposed to be doing now to encourage this year’s spent amaryllis to bloom next Christmas?
Sandra Martin, Bay Weekly editor
A Yes. Amaryllis takes tending all year long. But plan on it as next year’s Easter lily.
After the last frost, move the plant in the pot outdoors in full sun and plunge it in well-drained soil. Fertilize monthly with fish emulsion fertilizer to keep the plant growing vigorously all summer.
In the fall when the foliage turns yellow, move the potted bulb indoors and place in a cool dark place and allow the soil to completely dry.
Around the middle of February to the middle of March, the bulb will begin to sprout. Repot the bulb in fresh soil mixed 1:1 with compost so that only one-third of the bulb is buried in the rooting medium. Place near a south-facing window and water well. Thereafter, allow the soil to dry to the touch before watering. Do not fertilize the bulb until it has started flowering. Fertilizing before the flower buds are opening will delay bloom.
Generally, potting the bulb around Ash Wednesday will assure full bloom by Easter.
Horticultural Vinegar Explained
Q In your April 6 Bay Weekly column [Vol. xiv, No. 15], you mentioned horticultural vinegar to kill weeds. Evidently it is better for the environment. Is this something I can make myself?
Clair Knicley, by email
A No. Horticultural vinegar contains 20 percent acetic acid. The vinegar you purchase in the grocery stores is five percent. You would have to distill it to concentrate it.
Ask Dr. Gouin your questions at firstname.lastname@example.org. All questions will appear in Bay Weekly. Please include your name and address.