August is the time to start the fall garden in warm-winter zones, even though the heat makes it hard to believe. With no meaningful first frost, the timing here is driven by when conditions become favorable for cool-season crops; typically late October into November, and working backward from there. Cauliflower, cabbage, broccoli, and Brussels sprouts all need 8 to 10 weeks of indoor growing before they are ready to transplant, which puts their indoor start dates squarely in August. Short-day bulbing onions also go indoors this month for the long production season ahead. The fall harvest that defines gardening in these zones depends on what gets started now.

Indoors (fresh harvests):

  • Microgreens: peas, broccoli, sunflowers, arugula
  • Sprouts: alfalfa, broccoli, radish, mung
  • Herbs & greens under lights: chives, parsley, mint

Start indoors now for fall transplant:Broccoli, cauliflower, cabbage, Brussels sprouts. These need 8–10 weeks indoors before they're ready to set outside — starts made in August will go out in October as temperatures ease.

Start indoors now — long-season crops: Short-day bulbing onions. These need the longest lead time of any fall crop; starting them in August gives them the weeks they need before transplanting in September and October.

Crops that can be directly sown outdoors in August: Parsnip — use the pre-germination technique. Germinate seeds indoors in a cool location on a damp paper towel and move them to the garden before the radicle extends. Parsnip's long growing season makes the extra step worthwhile. In Hawaii and other tropical areas, heat-tolerant crops continue as in July.

Cover crops: Sunn hemp, cowpeas, sorghum-sudangrass — keep the soil covered through the remaining heat.

Tip: A Southern California zone 10 can be very different from a Florida zone 10. Consider checking with your state Extension Service office for more specific recommendations and guidelines.

Use your USDA zone as a guide. Microclimates matter — coastal/urban spots run warmer; high-elevation spots run colder.

50 100 true //store.trueleafmarket.com/cdn/shop/t/54/assets/review-fallback.json?v=33078429469613971781712858278
Legend: H for Heirloom, O for Organic, A for AAS Winner, F for staff favorites
393 Items
{ "manual": "Featured", "most-relevant": "Most relevant", "best-selling": "Best selling", "title-ascending": "Alphabetically, A-Z", "title-descending": "Alphabetically, Z-A", "price-ascending": "Price, low to high", "price-descending": "Price, high to low", "created-ascending": "Date, old to new", "created-descending": "Date, new to old" }
Lettuce Seeds - Leaf - Red Oakleaf - Clearance Seeds
-49%
Heirloom
Lettuce Seeds - Leaf - Red Oakleaf - Clearance Seeds
Starting at $50.00
basil in a basket surrounded by other vegetables.
-0
Basil Seeds - Salerno
Starting at $5.59
Cucamelon Seeds - Mexican Sour Gherkin - Clearance Seeds''
-68%
Heirloom
Cucamelon Seeds - Mexican Sour Gherkin - Clearance Seeds
Starting at $100.00
Dark purple basil in a nature background.
-0
Basil Seeds - Ravenna
Starting at $5.59
Green cucumbers growing on the vine in a garden, surrounded by green leaves and small yellow flowers.
-0
Organic
Cucumber Seeds - Straight 8 F1 Hybrid (Organic)
Starting at $4.69
Alyssum Seeds - Easter Bonnet Series MSPAlyssum Seeds - Easter Bonnet Series MSP
-0
Alyssum Seeds - Easter Bonnet Series MSP
Starting at $26.80
Melon Seeds - Oshiro Uri Numane - Clearance Seeds
Starting at $10.00
Shiso Seeds (Perilla) - Green (Organic)
Starting at $3.99
Watermelon Seeds - Mini - Splendor Hybrid
Starting at $5.39
[ { "featured_image": "files/1774370403_melon_pickling_oshiro_uri_numane_below_standard_low_germ_comp_50552343-78a4-45fe-8f3d-1f45e90a6bc0.jpg", "secondary_image": "", "price": 1000, "handle": "melon-seeds-oshiro-uri-numane-clearance-seeds", "title": "Melon Seeds - Oshiro Uri Numane - Clearance Seeds", "url": "/products/melon-seeds-oshiro-uri-numane-clearance-seeds", "available": false }, { "featured_image": "files/1774388358_lettuce_leaf_oakleaf_red_below_standard_low_germ_comp_70682ee6-b356-458c-a094-d7549c34b2b3.jpg", "secondary_image": "", "price": 5000, "handle": "lettuce-seeds-leaf-red-oakleaf-clearance-seeds", "title": "Lettuce Seeds - Leaf - Red Oakleaf - Clearance Seeds", "url": "/products/lettuce-seeds-leaf-red-oakleaf-clearance-seeds", "available": true }, { "featured_image": "files/1782919747_herb_basil_salerno_comp_d80b8075-6cb5-4fba-a05b-c4873e7939de.jpg", "secondary_image": "", "price": 559, "handle": "basil-seeds-salerno", "title": "Basil Seeds - Salerno", "url": "/products/basil-seeds-salerno", "available": true }, { "featured_image": "files/1782747107_cucamelon_aka_mexican_sour_gherkin_below_standard_low_germ_clearance_comp_37aec65e-740c-4212-a7e1-82761bec9e10.jpg", "secondary_image": "files/Cucamelon-Mexican-Sour-Gherkin-Licensed-wm-comp_1.jpg", "price": 10000, "handle": "cucamelon-seeds-mexican-sour-gherkin-clearance-seeds", "title": "Cucamelon Seeds - Mexican Sour Gherkin - Clearance Seeds", "url": "/products/cucamelon-seeds-mexican-sour-gherkin-clearance-seeds", "available": true }, { "featured_image": "files/1782920703_herb_basil_ravenna_comp_147a2c28-4dc0-47d0-90f7-216e0f6241da.jpg", "secondary_image": "", "price": 559, "handle": "basil-seeds-ravenna", "title": "Basil Seeds - Ravenna", "url": "/products/basil-seeds-ravenna", "available": true }, { "featured_image": "files/1782829513_cucumber_straight_8_elite_f1_organic_comp_e3863259-46af-4783-9275-2a1109898240.jpg", "secondary_image": "", "price": 469, "handle": "cucumber-seeds-straight-8-f1-hybrid-organic", "title": "Cucumber Seeds - Straight 8 F1 Hybrid (Organic)", "url": "/products/cucumber-seeds-straight-8-f1-hybrid-organic", "available": true }, { "featured_image": "files/alyssum-easter-bonnet-series-flower-seeds-Comp.jpg", "secondary_image": "products/alyssum-easter-bonnet-deep-pink-wm_700.jpg", "price": 2680, "handle": "alyssum-seeds-easter-bonnet-series-msp", "title": "Alyssum Seeds - Easter Bonnet Series MSP", "url": "/products/alyssum-seeds-easter-bonnet-series-msp", "available": true }, { "featured_image": "files/1774884354_shiso_perilla_green_comp_5d65d660-ff01-45b4-b390-dce1d153fa73.jpg", "secondary_image": "files/1774884353_shiso_perilla_green_seeds_comp_a66a5698-fea9-4ffb-94a6-1bef242a6eeb.jpg", "price": 399, "handle": "shiso-seeds-perilla-green-organic", "title": "Shiso Seeds (Perilla) - Green (Organic)", "url": "/products/shiso-seeds-perilla-green-organic", "available": false }, { "featured_image": "products/watermelon-splendor-f1-hybrid-l-com-wm.jpg", "secondary_image": "products/non-gmo-seed-bag-1-lb-com_da05c81a-946c-4525-92ce-31e9ffc56ef3.jpg", "price": 539, "handle": "watermelon-seeds-splendor-f1", "title": "Watermelon Seeds - Mini - Splendor Hybrid", "url": "/products/watermelon-seeds-splendor-f1", "available": false } ]