September is the month the garden turns. The heat eases, the light softens, and the fall garden takes over from summer. In Zone 8, September is for sowing hardy salads and roots, planting garlic, harvesting storage crops, and putting beds to work with cover crops. The summer garden is winding down; the fall garden is just getting going.
What September means in Zone 8
USDA Zone 8 runs through the southern United States, from parts of Texas, Louisiana, Georgia and South Carolina to the Pacific Northwest coast and parts of California. Winters are mild, with average winter lows of 10 to 20°F, and the growing season is long, which gives Zone 8 gardeners one of the most forgiving calendars in the country.
The dates that matter most are the frost averages. The average last spring frost in Zone 8 is Mar 1–15, and the average first autumn frost is Nov 15–Dec 1. These are USDA zone averages drawn from NOAA frost records, not exact dates for any one garden. Always check your local extension service and the forecast before planting tender crops outside. Use our frost date calculator for your zone’s averages.
September in Zone 8 is gentler than August: the heat eases, fall seeds germinate fast in warm soil, and the average first frost is still two months away. It is the best month of the year for sowing hardy salads, and garlic can go in now or in October.
September task list
- Sow spinach, lettuce, radishes, arugula, turnips and cilantro.
- Harvest winter squash, pumpkins, sweet potatoes and beans before frost.
- Plant garlic and shallots in prepared beds.
- Transplant lettuce, kale and chard seedlings.
- Sow cover crops, such as crimson clover or winter rye, on empty beds.
- Lift and store potatoes, and cure sweet potatoes and squash.
- Clean up spent plants, compost healthy material, and mulch beds.
What to start indoors in September
Start these under cover now, with strong light and steady moisture.
- Lettuce — matures in 45–60 days; hardy; soil pH 6.0–7.0.
- Parsley — matures in 70–90 days; hardy; soil pH 6.0–7.0.
- Chives — matures in 60–90 days; hardy; soil pH 6.0–7.0.
What to direct-sow in September
Sow these straight into prepared beds and water the seed row well.
- Spinach — matures in 40–50 days; hardy; soil pH 6.0–7.5.
- Lettuce — matures in 45–60 days; hardy; soil pH 6.0–7.0.
- Radishes — matures in 25–40 days; hardy; soil pH 6.0–7.0.
- Arugula — matures in 30–45 days; hardy; soil pH 6.0–7.0.
- Turnips — matures in 40–60 days; hardy; soil pH 6.0–7.0.
- Cilantro — matures in 45–60 days; hardy; soil pH 6.0–7.0.
- Carrots — matures in 60–80 days; hardy; soil pH 6.0–6.8.
What to transplant in September
Harden seedlings off for a week before planting out, and water them in well.
- Lettuce — matures in 45–60 days; hardy; soil pH 6.0–7.0.
- Kale — matures in 50–65 days; hardy; soil pH 6.0–7.5.
- Swiss chard — matures in 55–65 days; hardy; soil pH 6.0–7.0.
What to harvest in September
Pick little and often: regular picking keeps beans, squash and cucumbers producing.
- Sweet potatoes — tender, matures in 90–120 days.
- Butternut squash — tender, matures in 90–110 days.
- Pumpkins — tender, matures in 90–120 days.
- Bell peppers — tender, matures in 60–90 days.
- Okra — tender, matures in 50–65 days.
- Tomatoes — tender, matures in 60–85 days.
September planting at a glance
| Crop | What to do | Days to maturity | Cold tolerance | Spacing |
|---|---|---|---|---|
| Lettuce | Start indoors | 45–60 | hardy | 8–12 in |
| Parsley | Start indoors | 70–90 | hardy | 6–8 in |
| Chives | Start indoors | 60–90 | hardy | 6–8 in |
| Spinach | Direct sow | 40–50 | hardy | 4–6 in |
| Radishes | Direct sow | 25–40 | hardy | 2–3 in |
All figures are broad published ranges from standard horticultural references, and they vary by variety, soil and weather. Check your local extension service for advice on your own garden.
Soil, water and feeding in September
September soil is still warm, so seeds germinate fast, but the days are shorter, so growth is slower: sow fall crops early in the month. Spread compost on beds you are putting to rest and sow cover crops to protect the soil over winter. Water new sowings until established, then ease off as rain returns.
Frost and weather protection
September is when frost returns to the conversation in Zone 8. The average first autumn frost is Nov 15–Dec 1, so tender crops like tomatoes, peppers and basil are living on borrowed time: harvest them before the first cold night, and keep fleece ready. Hardy crops like kale, carrots and spinach shrug off a light frost and often taste sweeter after one. Check your local extension service and the forecast before leaving tender crops out overnight.
Pests and problems to watch
September pests are mostly slugs and cabbage whites on fall brassicas. Net brassicas, set slug traps, and clear fallen fruit that attracts wasps and fungal disease. Remove tomato plants once they stop producing: leaving them invites blight to overwinter.
Frequently asked questions
What can I plant in September in Zone 8?
Hardy salads and roots: spinach, lettuce, radishes, arugula, turnips, cilantro and garlic. It is also the month to sow cover crops on empty beds.
When should I harvest winter squash in Zone 8?
Before the average first frost, Nov 15–Dec 1. Harvest when the skin is hard enough that a fingernail will not dent it, and cure in a warm, dry place for a week or two.
Can I plant garlic in September in Zone 8?
Yes: garlic planted in autumn needs the cold winter to form bulbs, and it matures in 180 to 240 days. Plant cloves pointy-end up, about 6 inches apart, in well-drained soil.
Will a light frost hurt my fall crops?
Most fall crops handle a light frost well: kale, spinach, carrots and radishes often taste better after one. Tender crops like tomatoes, peppers and basil will not survive it, so harvest them first.
For the full year, browse the planting calendar hub. Nearby months: August in Zone 8, October in Zone 8, September in Zone 7. Use the garden planner to work out exact dates for your own garden.