Wednesday, June 30, 2010

July/August Hort Shorts

  • When harvested, a raspberry leaves the white “core” on the plant as the berry is pulled away. Blackberries take the “core” with them when harvested.
  • Apples produce a gas called ethylene during their ripening stage. This gas also helps tomatoes ripen. That is why tomatoes harvested in a mature green stage will ripen better if put into a tray with a few apples nearby.
  • Summer squash are those where the fruit is harvested in an immature stage of development. Rind, seeds and all are eaten. Winter squash are harvested when they are mature. Generally, only the rind is eaten.
  • A good crop of sweet corn will yield over 13,000 ears per acre.
  • Determinate plants grow to a certain size and quit. Indeterminate plants such as vines keep on growing indefinitely. Tomatoes and cucumbers come in both types.
  • Tomatoes are a fruit in the botanical sense. They are the structure resulting from the fertilization (pollination) of the plant ovary. Legally, for interstate commerce purposes, the tomato has been declared a vegetable.
  • Cucumbers and sweet corn are monoecious. They have separate male and female flowers on the same plant. On corn, the male is the tassel and the female flower is the silk. Female flowers on a cucumber vine have a small swelling at the base which will become the fruit after pollination. Male cucumber flowers appear first on the vine and do not have the swollen knob beneath the petals.
  • Ginkgo trees and holly are dioecious which means that they have separate male and female flowers found on different plants. To get holly berries you have to have one male for every three or four female plants. Avoid female ginkgo trees since the fruit has a bad odor.
  • Wild Cucumber Vine, Echinocystis lobata, is a vine found along country roads in the early fall. It has clusters of white flowers and star shaped leaves that resemble those of the sweetgum tree. Small, bur-like fruit that look like cucumbers will follow.

Pruning Oak Trees
In the past few years, a disease known as oak wilt has been rearing its ugly head in Michigan. The disease is especially virulent on trees in the red oak group (oaks with the pointed leaves) and less of a problem in white oaks (oaks with the rounded leaves). It acts similar to Dutch elm disease but, fortunately, is nowhere near as devastating. However, since it is a wilt disease, it is one of the few tree problems that, by itself, will kill an infected tree. Oak wilt is spread primarily by small beetles that travel from tree to tree. They are attracted to open wounds left after pruning or from storm damage. When they land on the wound to feed on the sap, they may also be spreading the oak wilt fungus spores from one tree to another. To help keep your trees healthy, avoid pruning oaks during the growing season i.e. when they have leaves on them. It is all right to prune them during the winter when they (and the insects) are dormant. If you must prune during the growing season or if storms break off branches, use a tree wound compound on the cuts. This has been shown to prevent the insects from feeding on the wound. It is important that the wounds be treated immediately after
being created to be effective.

Keep Vegetables Harvested
Cucumbers, tomatoes, peppers, egg plant, summer squash, snap beans, asparagus, broccoli and spinach will stop new production if overgrown fruit is left on the plant after it is ripe. Regular harvesting will extend production and increase the yield. Summer squash and cucumbers reach peak quality while they are still relatively small. Snap beans are best when the pods are nicely rounded but before they begin to bulge with seeds. So, keep the vines and plants cleared of ripened fruit and toss the overgrown stuff in the compost pile.