Most gardening calendars are written for zones 5–7. Zone 9 is its own world: summer heat tops 110°F in Phoenix, cool winters rarely freeze, and the growing calendar is inverted from the rest of the country.
Cool Season: October–March
This is your prime growing season. Temperatures stay 40–75°F — perfect for leafy greens, brassicas, and root vegetables. Plant: lettuce, kale, spinach, Swiss chard, broccoli, cauliflower, cabbage, carrots, beets, radishes, peas, cilantro, and parsley.
Transition Months: March–April and September–October
March and April bridge the cool/hot seasons. Tomatoes, peppers, and squash go in during this window — they'll produce before summer heat shuts them down. September–October is the reverse: plant fall crops as summer heat breaks.
Hot Season: May–September
Most vegetables fail above 95°F. Focus on heat-adapted crops: Armenian cucumber, yard-long beans, okra, sweet potato, Malabar spinach, and heat-tolerant pepper varieties. Provide afternoon shade for anything that will tolerate it. Drip irrigation is essential — overhead watering in 100°F heat causes leaf scorch and fungal issues.
