Southern California Coastal & Inland Valleys
Fertilize Vegetables Between Crops
When replanting areas where you've just harvested spring vegetables, follow heavy-feeding leafy vegetables like spinach and cabbage with nitrogen-replenishing legumes such as peas, beans, and soybeans; or plant a less-demanding root crop. Don't fertilize the soil again before succession plantings of beans or carrots, since excess nitrogen results in forked and hairy carrots and lush bean plants with few beans. Do add some compost before setting out spinach, kale, and lettuce, since you do want lush foliage in these crops.
Choosing Heavy-Producing Crops for Small Gardens
Some vegetables are more efficient than others, producing more food for the amount of garden space they use and the time they require from you. Carrots, cucumbers, onions, potatoes, summer squash, and tomatoes produce the most. Yields of cucumbers, squashes, and tomatoes can be even greater when they are grown on trellises, saving soil space for growing more crops.
Prevent Corn Smut
Plant the last batch of corn this month, as later plantings will probably have smut problems (those big, grey and black puffs of fungus in place of kernels) when harvested in September. Or you may choose to innoculate some of your corn with the fungus; it's a delicacy in Southwestern and Mexican cuisine.
Reducing Earworm Damage on Corn
Lessen earworm damage on corn by sprinkling lime or Bacillus thuringiensis (sold as Bt, Dipel, and Thuricide) onto the silks as soon as they begin to dry. Using mineral oil (another remedy) may spoil the corn. Insect-damaged ears should be carefully destroyed rather than composted or used for mulch, since you don't want to spread the problem throughout your garden.
Keep Soil Mulched
Keep adding more mulch throughout the summer to conserve water, keep roots cool, and foil weeds. Remember to water well before applying the mulch, or you'll insulate dry soil rather than moist soil. Pile mulch 2 to 6 inches deep under shrubs, trees, vines, flower, and vegetable beds. Let grass clippings dry out a bit before piling them (or just spread them thinly), or they'll clump into a mat that's impervious to later watering.