Five things to do in the garden this week:
Ornamentals: Coleus thrives from spring to fall and may even persist into winter. The plant is somewhat tricky to grow since it burns in too much sun and flounders in too much shade, so filtered sun is best. Since its roots are shallow, keep it away from trees and shrubs whose surface roots could interfere with its own. If blue flowers begin to appear, remove them since, underwhelming in appearance, they halt growth of the colorful foliage. Keep coleus happy with fish emulsion, which contains only 4-5% nitrogen, or another low-analysis fertilizer. An incalculable bonus of growing coleus is its ease of propagation. Detach a 3-4 inch shoot terminal, remove its bottom leaves, place it in a glass with a little water, and it will begin to grow roots this time of year within a week or two.
Fruit: It’s about time that you and I planted a Tamarillo. This is a small tree with a fairly rapid rate of growth. It may reach a height of 18 feet, but will typically grow half that size or less, depending on climate conditions. While it is meant for full sun, in our hot valleys it will require some shade. The fruit is egg-shaped, 2-4 inches long and half as wide. Flavor has been described as a combination of tart and sweet flavors with hints of guava, kiwi, passion fruit, and tomato. Tamarillo (Solanum betaceum) fruit is eaten like a grapefruit, sliced in half with the pulp, whose consistency is that of a tomato, scooped out. Its taste is too tart for some palates and is sometimes sweetened with sugar before consumption. Red fruit are more tart while orange to yellow fruit tend to be sweeter. Tamarillo seeds and starter plants are readily available through Internet vendors. This species displays some cold tolerance, but for safety’s sake it should be covered with burlap, row cover, or frost fabric when freezing weather is forecast.
Vegetables. Fall is for planting every sort of green vegetable, including kale and collard greens. For something exotic, experiment with a perennial tree kale and or tree collard. These seldom-seen plants can live for up to 20 years and grow up to 20 feet tall. You can find starter plants at projecttreecollard.org. The story of Deja’s tree collard business, recounted on the website, is as fascinating as the plants themselves. Although she sells a few different types, she recommends the purple tree collard since is rarely flowers and is therefore more prolific in collard leaf production.
Herbs. Chamomile (Matricaria recutita) is a cool-season herb and now is the time to plant it. Seeds germinate easily in average soil. Plants grow to a height of two to three feet and are covered with small daisy blooms. For storage, seal flowers in an air-tight jar or other sealed container. However, if you are sensitive to plants in the daisy family, such as ragweed, use chamomile flowers with caution.
A reader wrote that they had sprayed a soap and water solution on those yellow aphids that bother milkweed plants. The plant was severely damaged, although a few green shoots at the bottom remained. I imagine that the solution sprayed was too concentrated in whatever soap was used. In homemade insecticidal soap recipes, dish soap is customarily recommended and it could be effective if properly diluted in water. However, it is probably better to purchase insecticidal soap at the nursery since quality control of such products means the spray will be more reliable than a homemade equivalent. Still, I advised the milkweed gardener to nurture the few green shoots that remained since they could grow into robust stems before fall is over. As far as any pesticide is concerned, it’s a good idea to spray a little of it on a few leaves for test purposes before dousing the entire plant.