Los Angeles, CA

Los Angeles occupies zone 10b with an exceptionally long frost-free window: minimum winter temperatures rarely drop below 35 to 40°F. The last spring frost occurs around December 31, and the first fall frost arrives around December 28, meaning the practical frost-free growing season extends 365 days.

The dominant constraint is not winter cold but summer heat and water scarcity. The Mediterranean climate alternates between a mild, moderately wet winter (November through March) and a hot, dry summer (June through September). During summer, intense solar radiation and high temperatures stress cool-season crops and cause physiological problems: blossom-end rot in tomatoes, sunscald on peppers, and reduced flowering in beans.

Water availability is the second major limiting factor. Los Angeles' semi-arid climate demands reliable irrigation during the growing season, especially summer. Drought-tolerant crops like figs, rosemary, and basil thrive with minimal supplemental water, while vegetables require consistent moisture.

The year-round growing season is an asset but requires split thinking. Cool-season crops (tomatoes, peppers, eggplant) planted in late summer or early fall will grow through the mild winter and spring, avoiding peak summer heat. Heat-loving perennials like figs anchor the landscape and thrive during the season.

The two biggest challenges are summer heat stress and water availability. Tomatoes and peppers, the signature crops for Los Angeles gardeners, produce reliably from September through June but often fail or produce weakly from June through August without shade cloth and consistent irrigation. Blossom-end rot becomes common in tomatoes once temperatures exceed 85°F and watering becomes irregular. Peppers similarly drop flowers under heat stress.

The second challenge is the semi-arid climate's demand for consistent water supply. Summer irrigation is essential for vegetables but is often restricted due to regional water scarcity policies. Gardeners planning for these months need drought-tolerant alternatives: figs, rosemary, basil, and other Mediterranean crops that produce with minimal supplemental water.

A third challenge, often overlooked, is powdery mildew during the cool, damp months (November through February). Humidity spikes in winter, and poor air circulation in crowded plantings creates conditions for fungal pressure on squash, beans, and other susceptible crops.

Plant heat-sensitive crops in late summer for fall and spring production. Sow tomatoes, peppers, and eggplant seeds in July and August so transplants are ready to set out by late August or September. These crops will grow vigorously through the cool season and produce through winter and spring, avoiding the hottest months. This inverts the typical summer gardening schedule.

Use shade cloth for summer vegetables and mulch to conserve water. If growing summer crops (May through August), deploy 30 to 50% shade cloth over tomatoes and peppers starting in June. Mulch heavily (3 to 4 inches of wood chips) to slow summer evaporation and maintain soil moisture consistency, which prevents blossom-end rot.

Build perennial Mediterranean crops into the landscape. Figs, rosemary, basil, and other heat- and drought-tolerant perennials establish once and produce for years with minimal care, reducing reliance on seasonal irrigation and seed-starting labor. A fig tree can produce fruit year-round in zone 10b, with heaviest crops in spring and fall.