Fall Planting in July and August

When it's one hundred degrees outside gardeners are up with the roosters getting their watering and harvesting chores finished before the heat of the day. Sometimes I venture out mid-day to marvel at the busy pollinators. No doubt if we could translate their buzzing vibrations they'd tell us to "jjjjjuuusssstttttzzzzzssssttttaaayyyy indoors!" Got it, might as well go shopping for more seeds to plant.

The third season of vegetable planting is here. If you're new to Colorado, we generally consider early spring to the middle of May the first planting season - cool crops, followed by warm season crops from mid-May to early summer. The third or fall season includes both warm and cool season and starts in July or later, depending on crop maturity before first frost.

I typically use mid-October as the first frost or freeze date, so focus on crops that will mature in about sixty days to be on the safe side. The seed packet will list days to harvest. 

Check the chart below for plants that can be seeded now through August and into early September.

Tuck in seeds wherever there is room, even the landscape if you've got some open real estate. Try the shady side of taller crops like tomatoes or corn. If the area was growing crops prior, mix some all purpose fertilizer in the soil before seeding.

When it cools down some (nights in the 50s, days in the 80s) direct seed lettuce, spinach, arugula and radishes - the quicker maturing cool season crops.

Cool season vegetables and herbs that can be seeded right now include beets, Brussels sprouts, cabbage, cauliflower, cilantro, Swiss chard, collards, bunching onions, parsley, peas.

Warm season vegetables and herbs that can be seeded right now include basil, bush beans, slicing cucumber, okra, New Zealand spinach, summer squash.

Fall Season Vegetable Planting Calendar 
for the Colorado Front Range

Use of cold frames or tunnels help extend the season

CROP – COOL SEASON	DAYS TO EMERGE	DAYS TO MATURITY	FALL SEED BASED ON MID OCTOBER FREEZE NOTES
Arugula (herb) Eruca sativa	7-14 days	30-45 days	Mid-Aug
Arugula – wild or heirloom Diplotaxis tenuifolia	7-14 days	30-45 days	Mid-Aug
Asparagus Asparagus officinalis	14-21 days soak seeds prior	Perennial	Spring Plant
Artichoke – Imperial Star Cynara scolymus	10-15 days	85-100 days	Spring Plant
Beets Beta vulgaris	5-21 days	60-65 or sooner for leaves	Mid-July
Broccoli Brassica oleracea	7-14 days	45-75 variety differences	July fall direct seeding is recommended
Broccoli Raab Brassica rapa	4-14 days	35-45 days	End-July
Brussels Sprouts Brassica oleracea Gemmifera group	5-10 days	80-110 days	Early-July
Cabbage Brassica oleracea var capitita	7-12 days	60-80 days	Mid-July
Cabbage (Napa or Chinese) Brassica rapa var pekinensis	10-15 days	50-55 days	Mid-July
Cardoon Cynara cardunculus	10-15 days	100 days	Spring Plant
Carrots Daucus carota var sativus	10-25 days	65-75 days	Direct seed every 3 weeks until August 15
Cauliflower Brassica oleracea var botrytis	8-10 days	50-80 days variety differences	Mid-July
Celeriac Apium graveonlens	14-25 days	95 days	Spring Plant
Celery Apium graveonlens	14-25 days	80 days	Spring Plant
Cilantro (herb) Coriandrum sativum	10-20 days	50-55 days	Mid-July, likes cool weather
Chard-Swiss Beta vulgaris	5-10 days	25 days – baby leaves 50 days –  bunch	Spring-Summer-Early Fall
Chicory Cichorium intybus	14-21 days	65-70 days	Late July, prefers cool weather, moist soil
Chives Onion (herb) Allium schoenoprasum	10-15 days	Perennial	Spring-Summer, Early Fall
Chives Garlic (herb) Allium tuberosum	10-15 days	Perennial	Spring-Summer, Early Fall
Claytonia Claytonia perfoliata	7-14 days	40 days	Late August. Known as winter purslane, likes cool weather and soil
Collards Brassica oleracea	10-15 days	50-60 days	Mid-July
Cress Lepidium sativum	5-15 days	20-30 days	Early fall
Endive Cichorium endivia	7-10 days	60-70 days 35 days – baby leaves	Late summer, needs cool soil and temperatures
Escarole Cichorium endivia	7-10 days	45-60 days	Late summer, needs cool soil and temperatures
Fennel (herb) Foeniculum vulgare	14-21 days	90 days for bulbs, less for foliage	Mid-July
Garlic (herb) Allium sativum	10 days for warm fall	9 months for fall planted	From Mid-Sept to Mid-Oct
Greens – Baby varies	5-10 days	25-30	Seed through early fall
Horseradish Armoracia rusticana		Perennial	Harvest roots in late fall
Kale Brassica oleracea	5-10 days	50-55 days	Early August
Kale Greens Brassica oleracea	5-10 days	25-30 days or 7-14 days for micro -greens	Every two weeks until first fall frost
Kohlrabi Brassica oleracea (gongylodes group)	10-14 days	55 days	Early August
CROP – COOL SEASON	DAYS TO EMERGE	DAYS TO MATURITY	FALL SEED BASED ON MID OCTOBER FREEZE NOTES
Leek Allium ampeloprasum (porrum group)	7-14 days	40 days for baby leeks, 84-100 for full size	Mid-August for baby leeks, okay to harvest after a couple of frosts
Lettuce Loose- Leaf Latuca sativa	5-10 days	21-68 days many varieties	Every three weeks until early fall, seed in afternoon shade of other plants
Lettuce Cos or Romaine Latuca sativa	5-10 days	50-70 days	Every three weeks until early fall, seed in afternoon shade of other plants
Lettuce Crisphead or Iceberg (tight leaves) Latuca sativa	5-10 days	75 days	Every three weeks until early fall, seed in afternoon shade of other plants
Lettuce Butterhead or Bibb (loose leaves) Latuca sativa	5-10 days	65 days	Every three weeks until early fall, seed in afternoon shade of other plants
Mâche Valerianella locusta	10-20 days	45-60 days	Late-August, afternoon shade
Mizuna Brassica rapa var. Japonica	4-7 days	35-45 days 21 days baby leaves	Late-August, afternoon shade
Mustard Greens Brassica juncea	7-10 days	50 days 21 for baby leaves	July-early September
Onion Seeds Allium cepa	7-15 days	70-150 days per onion day length	Spring Plant
Onion Bulbs or Sets Allium cepa	7-15 days	100 days or 3-4 weeks for green onions	August to Fall
Onion Bunching (Scallion) Allium fistulosum	10-15 days	60-65 days	Mid-July
Onion Egyptian Allium cepa var. proliferum	10-14 days	Perennial	Spring Plant
Orach Atriplex hortensis	7-14 days	35 days	Late August. Like a warm-season spinach, tolerates heat, nice annual ornamental too
Microgreens INDOORS	4-7 days	10-21 days, harvest days vary per seed types	Many seeds to choose from, seed in shallow trays all year, esp. in winter
Pak choi or Bok choy Brassica rapa (Chinensis group)	5-10 days	30-50 days	Late July to mid-September
Parsley (herb) Petroselinum crispum	14-28 days	60-75 days	Mid-July, Soak seeds prior to seeding, prefers afternoon shade
Parsnips Pastinaca sativa	10-25 days	85-120 days	Harvest in fall after frosts for sweet flavor
Peas – shell, snap, snow Pisum sativum	5-10 days	50-65 days	Mid-July, soak seeds prior to sowing
Potato Tubers Solanum tuberosum	10-15 days	90-120	Spring Plant
Radicchio Cichorium intybus	7-10 days	60-90 days	Late summer, needs cool soil and temperatures
Radish Raphanus sativus	5-10 days	20-30 days	Late summer until first fall frost
Radish - Daikon Raphanus sativus	5-10 days	60 days	Harvest any size in late fall before ground freezes
Rhubarb Crowns Rheum rhabarbarum		Perennial	Spring Plant. Grow one full year before harvest
Rhubarb Seeds Rheum rhabarbarum	7-14 days	Perennial	Spring Plant Soak seeds before planting. Grow one full year before harvest
Rutabaga Brassica napus	4-7 days	90-100 days	Spring Plant
Shallots Allium cepa var. aggregatum	10-15 days	100 days	Zone 5 or warmer fall or spring plant, Zone 4 or colder spring plant
Spinach - Common Spinacia oleracea	6-10 days	30-45 days	Use bolt resistant varieties during heat of summer, cold hardy types can overwinter
Tatsoi Brassica rapa var. narinosa	5-10 days	21 days baby leaves, 45 full leaves	Sow up to three weeks before first fall frost
Turnip Brassica rapa	5-10 days	40-75 days	Sow late summer before first fall frost

 

CROP – WARM SEASON	DAYS TO EMERGE *indoor seeded for spring planting	DAYS TO MATURITY	FALL SEED BASED ON MID OCTOBER FREEZE NOTES
Basil  (herb) Ocimum basilicum	5-10 days	60-85 days Annual	Mid-July, basil is very frost sensitive
Bean Bush—Filet, Snap, Haricot, String, Shelling, Wax, Dry, Phaseolus vulgaris	8-10 days	55-65 days 70-75 shell 80-100 dry	Mid - Late July for early maturing
Bean Pole— Wax, Snap, Phaseolus vulgaris	6-12 days	60-65 days	Mid-Late July
Bean Lima Phaseolus lunatus	6-12 days	65-85 days	July for early maturing
Bean—Winged Bean Phaseolus tetragonolobus	6-12 days	65-85 days	July for early maturing
Bean—Scarlet Runner Phaseolus coccineus	6-12 days	65-85 days	July for early maturing
Bean—  Yard Long Vigna unguiculata	10-15 days	65-85 days	July for early maturing
Bean Cowpeas Vigna unguiculata	10-12 days	75 days	July
Corn, Sweet Zea mays hybrids	5-10 days	68-80 days	Spring Plant
Corn Ornamental Zea mays	5-10 days	85-120	Spring Plant Can be left out after several frosts, harvest when kernels are hard and glossy
Cucumber Slicing, pickling, specialty Cucumis sativus	5-10 days	48-65 days, depends on variety	Mid-July for short maturing
Edamame Glycine max	10-12 days	80-95 days	Spring Plant
*Eggplant Solanum melongena	10-21 days	60-80 days	Spring Plant
Ground Cherry Physalis pruinosa	14 days	75 days	Spring Plant
Melon- Cantaloupe, Canary, Muskmelon, Honeydew Cucumis melo	5-10 days	60-85 days	Spring Plant
Melon ‘Cucamelon’ Melothria scabra	7-21 days	65-80 days	July for early maturing
Okra Abelmoschus esculentus	10-15 days	55-65 days	Mid-July, soak seeds for a day prior to sowing, harvest when small - 3-4”
*Pepper–Bell, Sweet, Serrano, Cayenne, Jalapenos, Paprika, Ornamental Capsicum annuum	10-21 days	70-90 days	Spring Plant
*Pepper - Habanero, Bhut Jolokia Capsicum chinense	10-21 days	90-110 days	Spring Plant
*Pepper –  Tobasco Capsicum frutenscens	10-21 days	80 days	Spring Plant
Pumpkin Cucurbita maxima	5-14 days	95-120	Spring Plant
Pumpkin Cucurbita pepo	5-10 days	95	Spring Plant
Spinach - Malabar Basella alba	14-21 days	85 days	Late Spring Plant
Spinach – New Zealand Tetragonia expansa	10-20 days	50-60 days	Mid-July also known as perpetual spinach
Squash Summer—Yellow, Zucchini, Patty Pan, Round, Scallop, Calabacita     Cucurbita pepo	5-10 days	45-65 many varieties	Mid-July, harvest  when small! Enjoy the edible flowers
Squash Winter –Butternut, Buttercup, Kabocha, Hubbard, Lakota  Curcurbita maxima	5-10 days	85-110 days	Spring Plant Harvest before first fall frost, edible flowers
Squash Winter– Acorn, Delicata,  Spaghetti  Cucurbita pepo	5-10 days	85-110 days	Spring Plant Harvest before first fall frost
Squash Winter – Butternut Cucurbita moshata	5-10 days	85-110 days	Spring Plant Harvest before first fall frost
*Tomato Lycopersicon esculentum	5-10 days	60-110 depending on variety	Spring Plant
*Tomatillo Physalis philadelphica or ixocarpa	10-12 days	75-100	Spring Plant
Watermelon Citrullus lanatus	3-5 days	70-100 depending on variety	Spring Plant