With the hot, dry weather, all plants (except California natives and a few others) need to be watered more frequently. Even more water is required during a searing Santa Ana wind, which dries soil and plants. Dichondra lawns, which are shallow-rooted, need watering twice a week; deep-rooted Bermuda can get by with once a week. Water flower beds once or twice a week. Shallow-rooted shrubs and plants such as azaleas and ferns will do all right with a good soaking once a week; a hose soaker is ideal for these. Most trees and shrubs that are deep-rooted will do well with one deep irrigation a month. Keep water away from native oaks and fremontias as much as possible; soggy soil during warm weather causes fungus and root rot.
Streptocarpus (Cape primrose), Sinningia (gloxinia) and Saintpaulia , (African violet) are all members of the same family, gesneriads, and are easily grown from leaf cuttings. After cleaning up the plants, save the firm, green outside leaves to start new plants. Don't let them dry out as you do when propagating geraniums. Break the mid rib, and stick the leaf in Vermiculite up to the break. Place the pot in a clear plastic bag, keeping the plastic off the plants with supports. Moisture collecting on the inside of the plastic shows that it is humid enough. The temperature should range between 70 and 80. Make sure the cutting receives plenty of light but no direct sun. In about a month a new plant will appear.
Petunias usually start to look ragged about this time. Cutting off the ends will force the plants to put out new shoots near the center; new plants can be propagated from the cuttings. Using a high-nitrogen fertilizer pushes petunias into lush growth at the expense of bloom.
If the rhizomes of German bearded irises start crowding one another, divide them as soon as they finish blooming. They don't need it every year--some say that once every five years is enough. The irises ordered from an iris grower are only a single short rhizome, but when dividing at home leave two joined together by an old third one--sort of a "Y" shape--and they will become established faster and bloom sooner. When replanting, barely cover them with soil, pointing them in the direction you want them to grow. Wait until September to divide spuria irises, but cut off their dead leaves as soon as they turn brown.
Plumeria, which Hawaiians use for fragrant leis, was at one time said to be very difficult, if not impossible, to grow in Southern California. Today the plants can be found growing from Manhattan Beach to upper Sierra Madre. Because they like warmth, plant them where they can get the reflected heat from a south or west wall. When they drop their leaves, they need a little water.
Leatherleaf fern, Rumohra, is a favorite of florists, because it is among the few ferns that can be cut and last in water. Grown in a shade garden, it is not demanding as to water and humidity and will send out rhizomes and grow like a tall ground cover.
Grapefruit trees produce well in Southern California, except in the cooler coastal areas; the warmer the climate, the sweeter the fruit. Good varieties include 'Marsh,' a standard yellow grapefruit with large seedless fruit; 'Ruby,' similar to 'Marsh,' but with red flesh, and 'Redblush,' which has deep-red flesh and a pink blush to the rind.
A garden journal is a valuable tool for keeping horticultural records; it is particularly useful in recording information about the performances of different vegetable varieties. Data such as yield, plant vigor, maturity dates and insect problems is quite useful in planning the next season's garden.
Growing banana plants is risky in areas where winter temperatures dip below 30. However, when damage occurs and the warm weather returns, the plants will sprout new growth from their rhizomes. Varieties that produce good fruit include 'Ice Cream,' 'Apple' and 'Mexican Dwarf.' The first two are full-sized plants (16 feet); the latter has a compact plant habit
(about eight feet).
Okra has to be fresh and the pods have to be the right size for good eating. Pods should be three to four inches long; if allowed to grow longer they will be tough and stringy. The pods mature rapidly, harvest every day or every other day, wearing gloves to protect your hands from the plant's spines.