Zone 9A — August
What to Plant in August in Zone 9A
August in Zone 9A:
1 crop to start indoors,
1 to plant or direct sow outside, and
3 entering harvest window.
Last frost averages February 15. Reference city: Phoenix, AZ.
1 Start Indoors
1 Plant Outside
3 Harvest
Start Indoors in August
| Plant | Type | Start Indoors | Transplant Outside | Harvest Window |
|---|---|---|---|---|
| Garlic | garlic | Aug 12 | Aug 19 | Apr 16 – May 16 |
Plant Outside in August
| Plant | Type | Action | Target Date | Harvest Window |
|---|---|---|---|---|
| Garlic | garlic | Transplant | Aug 19 | Apr 16 – May 16 |
Harvest in August
| Plant | Type | Planted / Sown | Harvest Window |
|---|---|---|---|
| Crosne tubers | crosne | Mar 1 | Aug 28 – Oct 7 |
| Elephant garlic bulbs | elephant garlic | Mar 1 | Aug 28 – Oct 27 |
| Winter rye cover crop stands | winter rye | Mar 1 | Aug 28 – Oct 7 |
Key Tasks for August in Zone 9A
- 1 Start 1 variety indoors this month under grow lights or in a sunny south-facing window. Use a seed-starting mix and bottom heat (70–75°F) for best germination rates.
- 2 Harden off transplants before moving outdoors — set them outside in a sheltered spot for increasing hours over 7–10 days before planting in the ground.
- 3 Apply 2–3 inches of mulch around heat-sensitive crops to retain moisture and keep root zones cooler. Water deeply and less frequently rather than shallow daily watering.
- 4 Check soil moisture before watering — stick a finger 2 inches into the soil. Water only when the soil is dry at that depth. Consistent moisture is more important than frequency.
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