Planting calendar
August Planting Guide for Phoenix, AZ: Raised Beds, Containers, and In-Ground Gardens
In August, Phoenix gardeners can start planting heat-tolerant fall crops in raised beds, containers, and in-ground gardens. Focus on warm-season vegetables and herbs that thrive in late summer heat while preparing for the upcoming cooler months.
Plant now (quick list)
Okra, Sweet potatoes, Eggplant, Peppers, Melons, Basil, Malabar spinach, Southern peas
Plant now
- Okra
- Sweet potatoes
- Eggplant
- Peppers
- Melons
- Basil
- Malabar spinach
- Southern peas
- Tomatillos
- Butter beans
Start indoors
- Broccoli
- Cauliflower
- Cabbage
- Kale
- Lettuce
- Spinach
- Swiss chard
- Collard greens
Avoid
- Cool-season crops outdoors (lettuce, broccoli, cabbage)
- Root vegetables (carrots, beets) due to heat stress
- Beans (snap beans) as heat reduces yields
- Potatoes
- Brussels sprouts
Next 2 weeks
- Begin hardening off indoor seedlings
- Monitor soil moisture closely in containers
- Mulch raised beds to retain moisture
- Check for pests like aphids and whiteflies
- Water early morning or late evening to reduce evaporation
- Fertilize heat-loving crops every 2 weeks
- Prune leggy plants to encourage airflow
- Rotate crops in in-ground beds
- Prepare soil for fall planting by adding compost
- Inspect irrigation systems for efficiency
FAQs
Can I plant lettuce outdoors in August in Phoenix?
No, outdoor lettuce will struggle with the high heat; start lettuce indoors and transplant when temperatures cool in September.
How often should I water raised beds during August?
Water raised beds deeply 2-3 times per week, adjusting for high temperatures and soil moisture.
Are there any herbs that do well planted now?
Yes, heat-tolerant herbs like basil and Malabar spinach thrive when planted in August.
When should I start hardening off my indoor seedlings?
Begin hardening off seedlings about two weeks before transplanting outdoors, typically mid to late August.
Is mulching beneficial during August in Phoenix?
Absolutely, mulching helps retain soil moisture and keeps roots cooler in the intense summer heat.
Next steps
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