Citrus trees should be examined for scale. If you find it, purchase an oil spray from your local nursery, but never apply the spray during hot temperatures or when the trees are water-stressed. Also, if any sucker branches have appeared at the bases of the trunks, cut them off; if allowed to grow, they will sap the tree of energy.
Kohlrabi has a flavor that is often described as a blend of sweet turnip and cabbage, yet it is more subtle and delicate than both. When harvested young, it may be peeled and eaten raw like an apple; otherwise, it can be boiled. Now through the middle of fall is the time to plant it in Southern California gardens. 'Grand Duke,' 'Early White Vienna' and 'Early Purple Vienna' are good varieties. Plant kohlrabi seeds in an area of the garden that receives full sun, and it will be ready for harvest in 45 to 60 days.
Weeds, like vegetables, come in warm- and cool-season varieties. The cool-season weeds will begin making their appearance about now. Don't let them get established, because they will compete with vegetables for water and light, and rob the soil of nutrients; cut, pull, mulch or cultivate with vigilance. You can eliminate the need for much weeding by planting vegetables very close together in raised beds. Herbicides should not be utilized in the vegetable garden.