Bulbs that do best in our Mediterranean climate ― Western natives such as calochortus and dichelostemma, and South Africans such as homeria and tritonia ― are often hard to find. A number of online sources (telosrarebulbs.com, brentandbeckysbulbs.com, and easytogrowbulbs.com) offer good selections. To make sure you get the ones you want in time for fall planting, order early.
Water lilies just may be the best reason for having a water garden, and now’s a good time to plant them. Hardy types are the easiest to grow, but tropical varieties bloom longer. Shop for a wide selection at Van Ness Water Gardens in Upland.
Grow pricey veggies for less. Sunset climate zones 18–24 can still sow seeds of beans, beets, and carrots. To get the best value for your water bill and time investment, grow something that’s hard to find or expensive at the supermarket, such as ‘Golden’ beets, ‘Sequoia’ beans (a purple Romano type), or ‘Atomic Red’ carrots. All these varieties are available from John Scheepers Kitchen Garden Seeds.
Grow an evergreen vine such as blood red trumpet vine (Distictis buccinatoria) to cover a pergola; a fence ornament like coral vine (Antigonon leptopus) or passion flower; or a modest grower such as Mandevilla to train on a trellis in a pot. Or, to delight a child, start scarlet runner beans or morning glories on a tipi made of bamboo stakes.
Plant Thai basil and cilantro now, and you’ll have fresh herbs all summer and beyond. Both annuals love sun and ample water, and do well in pots. Start basil from seedlings; to prolong leaf production, pinch off flower spikes as they develop, or let them go to enjoy the purple blooms. Because cilantro germinates quickly, sow seeds directly in the container. Begin harvesting when plants reach 6 inches tall; if you live in the low desert, wait to sow until fall.
Hose down summer-weary plants occasionally to diminish insect pests and dust. Clean up mineral deposits on dark succulents such as Aeonium arobreum ‘Zwartkop’ by gently wiping leaves with a soft cloth soaked in distilled water. Also feed all actively growing succulents (which most are) with either a cactus fertilizer or an all-purpose liquid fertilizer diluted to one-quarter strength.
Treat blossom-end rot. The dark brown sunken areas that develop on the bottoms of tomatoes are caused by inadequate calcium uptake, often the result of uneven watering. Irrigate plants deeply every five to seven days, and mulch around plants to retain moisture between irrigations. Avoid high-nitrogen fertilizers, which tend to block calcium uptake. If your tomatoes are still afflicted after treatment, try spraying foliage with seaweed extract to supply some calcium directly to the leaves.
Roses, lawns, annuals, perennials, container plants, and just about anything actively growing will benefit from a balanced fertilizer. Don’t feed natives or Mediterranean plants, though, as this is their dormant period.
If your coral tree (Erythrina) is growing too rapidly, now’s the best time to prune. Shorten long shoots by a third to a half, and remove any crossing branches. If you can, reduce irrigation ― this will slow down growth and may increase flowering too.
Control bougainvillea looper. If leaves are severely scalloped, this tropical caterpillar is probably the cause. Treat plants with an organic insecticide containing spinosad.
Examine the undersides of leaves of target plants such as fuchsia, hibiscus, and plumeria for white, waxy spirals where the giant whitefly eggs are deposited. Remove affected leaves, bag them in plastic, and dispose, or wash away the spirals with a strong stream of water.
Enclose trees with bird netting or fabric row covers (available at most nurseries) to protect your crops. The next best thing is tying Mylar flash tape on tree branches.