What to Plant in August 2026 ▷ US Fall Garden Guide

August: the pivot into the fall garden

August carries three parallel workstreams: maintaining the peak summer production (tomatoes, peppers, beans, squash still harvesting daily), transplanting fall crops (the brassicas started indoors in early July are now garden-ready), and direct-sowing cool-season greens and roots (lettuce, spinach, arugula, radishes, carrots, turnips, beets). The first is familiar; the second and third are what separate average gardeners from those with full pantries through December.

The soil story changes too. July soil at 4 inches was often 85–95°F — too hot for lettuce and spinach to germinate reliably. August soil drops into the 75–85°F range, especially under mulch or shade cloth, which is nearly perfect for cool-season seed emergence. Couple that with nights dropping below 70°F in most non-tropical zones and the same seeds that refused to come up in July now germinate in 5–7 days. This window is short — usually 3–4 weeks — but it is the most productive sowing period of the whole year for greens.

What to plant in August by USDA hardiness zone

Zone 5–6: fall transplant window and final direct sowings

Zone 5–6 (upper Midwest, New England, Great Plains, mountain West) has a tight August window because first frost is approaching in late September or early October. The priority is getting fall transplants in the ground by mid-August and direct-sowing fast-maturing crops before August 20.

Plant in August (Zone 5–6): transplant broccoli, cauliflower, cabbage, Brussels sprouts, kohlrabi and fall kale from July-started seedlings in the first two weeks; direct-sow lettuce, arugula, spinach, radishes, turnips and fall carrots through August 15; direct-sow fall peas (Oregon Sugar Pod, Green Arrow) first week of August for October harvest; final succession of bush beans (through August 5 only); Asian greens (tatsoi, pak choi, mizuna) all month under light shade; heat-tolerant lettuce varieties (Jericho, Nevada) under 30–50% shade until nights cool; swiss chard and collards from transplants; final plantings of dill and cilantro (bolt-resistant fall varieties); garlic bed preparation and seed garlic ordering. Avoid: warm-season crops (tomatoes, peppers, beans beyond August 5, cucumbers, squash).

Zone 7–8: peak fall planting month

Zone 7–8 (mid-Atlantic, Pacific Northwest lowlands, Southeast, lower Midwest) has the most productive August of any zone. First frost is typically late October to mid-November, giving 10–14 weeks of growing time after August planting. Both fall transplants and a full direct-sow schedule fit comfortably.

Plant in August (Zone 7–8): transplant the full fall brassica lineup — broccoli, cauliflower, cabbage, Brussels sprouts, kohlrabi, kale and collards from July-started seedlings, mid to late August; direct-sow lettuce, arugula, mustard greens, spinach (after August 15), radishes, turnips, beets, fall carrots and kohlrabi all month; sow fall peas for October harvest; start fall tomatoes and peppers from transplants in Zone 8 (heat-set varieties like Heatmaster, Solar Flare, Carolina Gold, Big Beef); sow bush beans through August 15; Asian greens and chicories; Swiss chard, collards and perpetual spinach; herb succession (dill, cilantro, parsley); prepare garlic bed and order seed garlic; overwintering onion seeds (short-day varieties in Zone 8+ only).

Zone 9–11: the second main growing season begins

In Zone 9–11 (Florida, Gulf Coast, Southern California, desert Southwest, Hawaii), August marks the start of the second main growing season of the year. The first hints of cooler nights appear in late August across inland areas, and Florida/Gulf gardeners begin what is essentially their "spring" — the fall-winter-spring growing season that runs through April.

Plant in August (Zone 9–11): start fall tomato transplants (plant last week of August through mid-September — heat-set varieties only: Solar Fire, Phoenix, Heatmaster, Florida 91); start pepper transplants (bell, jalapeño, habanero — all produce heavily through winter in true tropical zones); eggplant transplants for fall production; cucumbers (August 15 onward under light shade); summer squash second season; green beans (direct sow late August); okra final planting; Southern peas and cowpeas through mid-August; fall herb succession (basil, cilantro, parsley in shade); tropical greens (Malabar spinach, amaranth, Okinawa spinach continuing). Begin seeding fall/winter cool-season crops for Zone 9: broccoli, cauliflower, cabbage transplants late August for October planting; lettuce direct-sown last week of August in shade.

Transplanting fall brassicas in August

The fall brassica transplant window in Zone 5–7 runs roughly August 1 to August 25. Miss it and there is not enough cool-weather growing time before hard frost. Hit it correctly and September–November harvests of broccoli, cauliflower, cabbage and Brussels sprouts rival anything spring produces — often exceeding spring flavor and head size because the crops mature in cooling nights rather than warming days.

• Broccoli: transplant 18 inches apart in rich soil amended with 2–3 inches of compost. Water deeply at planting, shade for 7–10 days, mulch 3 inches deep with straw or shredded leaves. Expect first heads 55–65 days from transplant — late September to mid-October in Zone 5–7.
• Cauliflower: heavier feeder than broccoli — side-dress with compost or balanced fertilizer 3 weeks after transplant. Self-blanching varieties (Snow Crown, Amazing) avoid the tying step; traditional varieties need outer leaves tied over developing heads to prevent yellowing from sun exposure.
• Cabbage: 24-inch spacing for full-size varieties, 18 inches for mini-cabbages. Fall cabbage is consistently sweeter than spring cabbage. Red varieties (Ruby Perfection, Red Express) store 3+ months in cool conditions — excellent for root cellar or extra refrigerator space.
• Brussels sprouts: plant the healthiest transplants only — Brussels sprouts need the longest season of any brassica (90–110 days) and weak starts never recover. Space 24 inches apart, stake in windy sites, and harvest from the bottom up once lower sprouts reach marble size. Frost sweetens them dramatically.
• Kohlrabi: fastest fall brassica — ready in 55–65 days. Harvest young (tennis-ball size) for best texture; larger bulbs turn woody and fibrous. White and purple varieties both work; flavor is identical.
• Kale and collards: plant transplants 18 inches apart for full-size leaves, closer for baby leaf harvests. Both sweeten dramatically after light frost — the first frost of October usually transforms kale from bitter to dessert-level sweet.

Cool-season crops to direct-sow in August

August direct sowing is the most productive seed window of the whole year for cool-season crops. Soil is warm enough for 5–7 day germination, nights are cooling toward ideal growing temperatures, and bolting is no longer a risk because days are shortening rather than lengthening. The secret is shade cloth in the first 2 weeks (40–50% during germination and first true leaves) and consistent moisture — never let the soil surface dry out during germination.

• Lettuce: August sowings produce perfect fall harvests. Leaf lettuces (Black Seed Simpson, Red Sails, Salad Bowl) mature 45–50 days; butterheads (Buttercrunch, Nancy) 55–60 days; romaines (Coastal Star, Paris Island Cos) 65–70 days. Succession sow every 10 days through September.
• Spinach: needs soil below 75°F to germinate. Wait until mid-August in Zone 5–6, late August in Zone 7. Bloomsdale Long Standing, Tyee and Space F1 are reliable fall varieties. Overwinters under row cover in Zone 7+ for early-spring harvest.
• Arugula: fastest fall crop — 25–30 days from seed to harvest. Astro and Sylvetta varieties handle late-summer heat best. Continuous sowings every 2 weeks keep production through first hard frost.
• Radishes: 25–30 days. French Breakfast, Cherry Belle and Watermelon radish all do well. Fall radishes are crisper than spring — slower growth in cooling nights produces denser roots.
• Turnips: 35–50 days for roots, 25 days for greens. Purple Top White Globe and Hakurei (salad turnip) are both excellent. Fall turnips are sweeter than spring — frost exposure converts starches to sugars.
• Beets: 50–65 days. Detroit Dark Red, Chioggia and Golden all perform well in fall. The greens are edible from 30 days on — an added harvest while roots develop.
• Carrots: 60–75 days. Direct-sow the first two weeks of August in Zone 5–7 for fall harvest; under 50% shade cloth until germination is established. Deep pots or raised beds produce the straightest roots.
• Asian greens: tatsoi, pak choi, mizuna and bok choy all thrive in August soil. 30–45 days to harvest. More bolt-resistant than lettuce through warm spells.

Garlic, bulbs and overwintering crops

August is the planning month for garlic even though planting happens in October or November. Seed garlic sells out at specialty suppliers by September, so order now for October delivery. The two main categories:

• Hardneck garlic (Zone 3–7): produces scapes in early summer, forms 4–8 large cloves per bulb, stores 4–6 months. Favorites: Music (mild), German Extra Hardy (hot), Chesnok Red (classic), Metechi (extra hot).
• Softneck garlic (Zone 7–10): braidable, stores 8–12 months, produces more small cloves per bulb. Favorites: Inchelium Red (mild, Zone 9 champion), California Early (grocery standard), Silverskin (longest storage).

Prepare the garlic bed in August: clear spent summer crops, amend with 2–3 inches of finished compost, work in a handful of bone meal or balanced fertilizer per 10 square feet, and cover with a thick straw mulch to suppress weeds until planting. Spring-flowering bulbs (tulips, daffodils, hyacinths, crocus, alliums) also need August ordering. Saffron crocus (Crocus sativus) is a unique August-planted exception — corms planted the first two weeks of August bloom and produce saffron threads in October.

Fall tomatoes and peppers in Zone 8+

In Zone 8 and warmer, August is the month to start fall tomatoes and peppers. The goal is harvest starting mid-October through first frost (Zone 8–9) or all winter (Zone 10–11). Key principles differ from spring planting:

• Variety selection is critical. Only heat-set tomato varieties produce fruit during the 90°F+ August–September heat: Heatmaster, Solar Flare, Solar Fire, Phoenix, Florida 91, Carolina Gold, Sun Leaper. Standard spring varieties drop blossoms above 90°F and never recover.
• Plant transplants only. No time to start from seed — buy 6-week-old transplants from nurseries. Deep-plant (bury 2/3 of the stem) for maximum root mass.
• Install shade cloth for the first 2 weeks. 30–40% shade prevents transplant shock and boosts first fruit set. Remove once nights consistently drop below 70°F.
• Irrigate aggressively at establishment. Daily deep watering for the first 10 days, then every 2–3 days under drip irrigation. Soil must not dry out while roots establish.
• Peppers are easier than tomatoes. Peppers actually prefer late-summer planting. Bell, banana, jalapeño, habanero and cayenne all transplant well in August and produce heavy crops through December in Zone 9–10.

August planting table by zone

Crop	Zone 5–6	Zone 7–8	Zone 9–11
Fall brassicas (transplant)	✅ Week 1–2	✅ Mid–late	⚠️ Start indoors
Lettuce (direct sow)	✅ Through Aug 15	✅ All month	⚠️ Last week only
Spinach (direct sow)	✅ Mid–late Aug	✅ Late Aug	❌ Wait for Sept
Radishes / turnips / beets	✅ All month	✅ All month	⚠️ Last week
Carrots (fall)	✅ Week 1–2	✅ All month	❌ Wait
Fall peas (direct sow)	✅ Week 1	✅ Mid–late Aug	❌
Bush beans (final)	⚠️ Through Aug 5	✅ Through Aug 15	✅ Late Aug
Fall tomatoes (transplant)	❌	⚠️ Zone 8 only	✅ Late Aug
Fall peppers (transplant)	❌	⚠️ Zone 8 only	✅ All month
Garlic (order seed)	✅ All month	✅ All month	✅ All month
Asian greens (direct sow)	✅ All month	✅ All month	⚠️ Last week

August pest and disease management

August is peak pest pressure in most American gardens. Populations have been building all summer and reach their largest numbers just as the fall garden is most vulnerable — newly germinated seedlings and freshly transplanted brassicas look like a buffet. The top August threats and response protocols:

• Spider mites: fine webbing and bronze stippling on leaf undersides of beans, tomatoes, squash and peppers. Treat with forceful water sprays every 2–3 days, or insecticidal soap weekly. Predatory mite releases work only if daytime temperatures drop below 90°F.
• Cabbage worms and loopers: will target every fall brassica transplant immediately. Hand-pick, or apply Bt (Bacillus thuringiensis) spray weekly starting at transplant. Row cover over fall brassicas is the most effective prevention — install at transplant, remove at harvest.
• Flea beetles: pepper eggplant and brassica seedlings with tiny shotgun holes. Diatomaceous earth at planting, kaolin clay spray, or floating row cover all work. Transplants recover faster than seedlings.
• Squash vine borers: if you see wilting in the squash patch, the borers are already inside. Cut lengthwise along the stem with a sharp knife, remove the grub, bury the damaged section in soil to regrow roots.
• Tomato hornworms: 4-inch green caterpillars that defoliate plants overnight. Scout at dawn or dusk (easier to spot). If you see small white cocoons on the worm — leave it; that is a parasitic wasp raising a new generation of beneficials.
• Late blight (tomatoes/potatoes): dark water-soaked lesions on leaves, often after humid weather. Remove affected foliage immediately, avoid overhead watering, and consider copper spray. Severely infected plants should be pulled and bagged (not composted).
• Powdery mildew: white powder on squash, cucumber and bean leaves. Weekly 1:10 milk-to-water spray is surprisingly effective, or sulfur-based fungicide in cool weather. Resistant varieties exist for most crops.

Watering in August: transitioning from survival to growth

August watering is a hybrid of July survival mode and fall establishment mode. Early-August heat waves still require the July playbook (dawn deep watering, aggressive mulch, drip irrigation); late August cooler nights allow a shift to evening watering and lighter frequencies. Key rules:

• New fall transplants: daily water for the first 7 days, every other day for the next 10 days, then transition to standard 2–3x per week deep watering. Brassicas especially need consistent moisture to avoid bolting.
• Direct-sown cool crops: surface moisture is everything during germination. Mist or sprinkle twice daily until emergence, then shift to deeper less-frequent watering. Never let the top half-inch of soil dry out before seedlings emerge.
• Established summer crops: continue July-style deep watering for tomatoes, peppers, beans and squash. Fruit development during August heat is entirely water-dependent — skipping water = blossom end rot, cracked tomatoes, tough beans.
• Mulch depth: refresh anything that has decomposed below 2 inches. Straw, shredded leaves, wood chips or grass clippings all work. Bare soil in August loses 2–3x more water to evaporation than mulched soil.
• Drip irrigation is still the standard. If you have not installed it yet, August is still worth doing — you will benefit through September and every future season. Ensure filters are clean (algae buildup is common in August).

Common mistakes when planting in August

The failures that show up repeatedly in August gardens:

1. Skipping the fall brassica transplant window. The biggest single August mistake. If you did not start seeds in July, nurseries sell fall transplants throughout August — no excuse to skip. A full brassica garden in September–November is the reward for 2 hours of August transplanting work.
2. Direct-sowing spinach too early. Spinach needs soil below 75°F to germinate. Zone 7–8 gardeners who try August 1 sowings get sparse germination. Wait until August 20 or later, or refrigerator-prime the seeds (soak, then chill 5–7 days).
3. No shade cloth for August germination. Even in Zone 5–6, daytime highs often exceed 85°F in early August. Direct-sown lettuce, arugula and spinach will fail without 40–50% shade during germination and first-true-leaf stages.
4. Planting standard tomato varieties as fall crops. In Zone 8+, only heat-set varieties (Heatmaster, Solar Flare, Solar Fire, Phoenix) produce during late-August through September heat. Standard varieties drop blossoms and never recover.
5. Neglecting the garlic order. Specialty seed garlic sells out in September. Order in August for October delivery. Grocery-store garlic works in emergencies but underperforms specialty varieties by 30–50% in bulb size.
6. Forgetting row cover at brassica transplant. Cabbage worms, loopers and flea beetles find fall brassicas within 24 hours of transplant. Install row cover at planting or expect to lose 20–40% of leaf area in the first two weeks.
7. Ignoring August soil amendment. Soil is exhausted after 3 months of summer production. Top-dress beds with 1–2 inches of compost before fall transplanting — the nutrition boost dramatically increases fall yields.

Frequently asked questions about August planting

FAQ: What to Plant in August

Is August too late to plant a vegetable garden?

August is not too late — it is the single most important month for fall gardening in most of the US. Three parallel streams matter: (1) transplanting the fall brassicas started indoors in July (broccoli, cauliflower, cabbage, Brussels sprouts) into the cooling mid-August soil. (2) Direct-sowing cool-season crops for fall harvest — lettuce, spinach, arugula, radishes, turnips, beets, carrots, kale and Asian greens all germinate better now than in May because soil is warm enough for fast emergence but nights are cooling. (3) In Zone 9–11, August is when the second main growing season begins: tomatoes, peppers and eggplants go in as transplants for an October–December harvest. What is too late in August: spring brassica seed starts (that window closed in July) and warm-season crops in Zone 5–7 (not enough frost-free days remain).

When should I plant fall lettuce, spinach and greens?

The August direct-sowing window for cool-season greens is the most productive of the whole year for most gardeners. Target dates: lettuce August 1–20 in Zone 5–7, August 15 onwards in Zone 7–8, September in Zone 9–11. Spinach needs soil below 75°F for germination — wait until mid-August in Zone 5–6, late August in Zone 7 and use the refrigerator seed priming trick if germination stalls (soak seeds, then refrigerate 5–7 days before sowing). Arugula, mustard greens, kale and Asian greens (tatsoi, pak choi, mizuna) all thrive in August plantings. Use 30–50% shade cloth during germination if daytime highs still exceed 85°F; remove it as nights drop below 65°F. Fall greens outperform spring greens because they mature as days shorten — bolting risk disappears.

Which fall crops should I transplant in August?

The brassicas you started from seed in early July are now 4–6 weeks old and ready for the garden. Transplant in mid-to-late August once soil temperatures drop below 80°F at 4 inches deep — measure early morning, not afternoon. Priority transplants: broccoli (Belstar, Arcadia, Green Magic), cauliflower (Snow Crown, Amazing), cabbage (Ruby Perfection, Early Jersey Wakefield), Brussels sprouts (Hestia, Dagan), kohlrabi (Kossak) and fall kale (Winterbor, Lacinato). Water transplants deeply at planting, shade them for the first 7–10 days, and mulch heavily. These will mature September through November and most actually sweeten after light frost. If you skipped the July seed start, most nurseries sell fall brassica transplants throughout August — a perfectly acceptable shortcut.

When do I plant garlic and fall bulbs?

Garlic planning starts in August even though actual planting happens October–November. In August: order your seed garlic from a specialty supplier (hardneck varieties like Music, German Extra Hardy, Chesnok Red for Zone 3–7; softneck varieties like Inchelium Red, California Early for Zone 8+). Nurseries sell out by September. Prepare the garlic bed now by clearing spent summer crops, amending with 2–3 inches of compost, and covering with straw mulch to suppress weeds until planting. Spring-flowering bulbs (tulips, daffodils, hyacinths, crocus) also need August ordering for October–November planting. Saffron crocus (Crocus sativus) is an August exception — corms planted in early August bloom and produce saffron threads in October. Garlic planted 4–6 weeks before hard frost produces dramatically larger bulbs than spring-planted garlic.

What should I do about pests and disease in August?

August is peak pest pressure month. Spider mites explode in hot dry conditions — check the underside of tomato, bean and squash leaves for fine webbing and bronze stippling. Treat with strong water blasts every 2–3 days or insecticidal soap. Whiteflies swarm in Zone 8+ gardens — yellow sticky traps catch enough to monitor populations. Squash vine borers have laid eggs by now; the borers are inside the stems. Tomato hornworms reach 4 inches and can defoliate plants overnight — scout at dawn or dusk. Late blight appears on tomatoes in humid regions; remove affected foliage immediately and avoid overhead watering. Powdery mildew on squash, cucumbers and beans — apply 1:10 milk-to-water spray weekly or switch to resistant varieties for fall succession. August is too hot for most biological controls (beneficial insect releases), so monitoring and mechanical removal matter more than sprays.