When to start garden seeds

Starting seeds indoors is how many gardeners in Central Kansas grow the specific varieties of vegetable and flowers they enjoy or prefer. The trick is to start seeds indoors at the right time (not too early or late) to allow the seedlings to reach a good transplant size for the garden at the correct time of planting. There is always some flexibility, but knowing the timeframe for seed starting is important. Cool season veggies are often started indoors by early to mid- February, while warm season crops are started indoors by mid to late March or after.

Here are some examples for common veggies based on the 2021 calendar

Vegetable	Start seeds indoors	Transplant into garden
Cabbage, Broccoli, Cauliflower	January 29, 2022	March 26, 2022
Lettuce (if using transplants)	January 29,2022	March 26, 2022
Tomatoes	March 19, 2022	May 7, 2022
Peppers	March 12, 2022	May 7, 2022
Squash, cucumber	April 23, 2022	May 14, 2022

The following tables provide general timeframes for seed starting in Central Kansas.

Vegetable	Start seeds indoors	Germination Time	Growing Temperature	Weeks to grow indoors before transplanting	Comments
Broccoli	Early February	5 to 11 days	50 to 60 degrees F	7 to 8	Tolerates light frost after hardening.
Brussels sprouts	mid to late February	5 to 11 days	50 to 60 degrees F	6 to 7	Tolerates light frost after hardening.
Cabbage	Early February	5 to 11 days	50 to 60 degrees F	7 to 8	Tolerates light frost after hardening.
Cauliflower	Early February	5 to 11 days	50 to 60 degrees F	7 to 8	Tolerates light frost after hardening.
*Cucumber	Late April	6 days	60 to 62 degrees F	3 to 4	Sow in pots. Keep warm at all times.
Eggplant	Late March	7 to 15 days	62 to 65 degrees F	7 to 8	Keep Warm
Head Lettuce	Early February	5 to 11 days	50 to 60 degrees F	6 to 7	Tolerates light frost after hardening.
**Kale/Collards	Early February	12 days	50 to 60 degrees F	6 to 7	Tolerates light frost after hardening.
*Muskmelon	Late April	8 days	60 to 62 degrees F	3 to 4	Sow in pots. Keep warm
*Okra	Late April	8 to 14 days	60 to 62 degrees F	4 to 5	Sow in pots. Keep warm
Pepper	mid to late March	8 to 14 days	62 to 65 degrees F	7 to 8	Keep warm.
*Pumpkin	Late April	8 days	60 degrees F	4 to 5	Sow in pots. Keep warm
*Squash	Late April	8 days	60 to 62 degrees F	3 to 4	Sow in pots. Keep warm
Tomato	Late March	8 to 14 days	62 to 65 degrees F	6 to 7	Keep warm.
Watermelon	Late April	8 days	60 to 62 degrees F	3 to 4 – pots	Sow in pots. Keep warm

*These crops may also be direct seeded into the garden when soil temps reach 60 degrees

**These crops may also be direct seeded into the garden when soil temps reach 45 to 50 degrees

Several other crops not listed such as sweet corn, green beans, beets, or radish are also directly seeded into the garden at the proper soil temps

Flowers	Start seeds indoors	Germination time	Growing temperature	Crop time- weeks	Comments
Ageratum	Mid March	5 to 9 days	60 to 65 degrees F	7 to 8	Needs light to germinate.
Alyssum, sweet	Mid March	4 to 9 days	50 to 55 degrees F	7 to 8	Needs light to germinate.
Aster	late March	8 to 9 days	60 to 62 degrees F	6 to 7
Celosia	Early to mid March	6 to 11 days	65 to 68 degrees F	6 to 8	Don’t grow cool.
Cleome	Mid March	10 to 13 days	70 to 75 degrees F	6 to 8	Transplant before flowering.
Coleus	Early to mid March	8 to 11 days	65 to 75 degrees F	6 to 8	Needs light to germinate.
Cosmos	Early-April	6 days	65 degrees F	4 to 6
Dianthus	Early March	5 to 8 days	50 to 55 degrees F	10	Cover seeds lightly. Grow cool.
Dusty Miller	Early March	11 to 16 days	60 to 65 degrees F	9 to 10	Needs light to germinate.
Geranium seed	Early Feb	7 to 12 days	60 to 65 degrees F	12	Best if grown in small pot.
Gomphrena	Mid March	10 to 15 days	68 degrees F	8 to 10
Impatiens	Early to mid February	15 to 19 days	58 to 60 degrees F	10 to 12	Cover seeds lightly.
Lobelia	Early Feb	15 to 21 days	60 degrees F	11 to 12	Needs light to germinate.
Marigold	Early April	5 to 8 days	65 to 68 degrees F	6 to 7	Tall types require more time.
Melampodium	Early April	7 to 11 days	60 to 62 degrees F	7 to 8
Nicotiana	Late March	10 to 13 days	60 to 62 degrees F	8	Needs light to germinate.
Pansy/Viola	Early to mid-Jan	6 to 13 days	50 to 55 degrees F	12	Grow at cool temperatures.
Orn. Pepper	mid to late March	8 to 13 days	60 degrees F	9 to 10
Petunia	Late Feb	6 to 13 days	55 to 60 degrees F	10	Needs light to germinate.
Phlox, annual	Late March	6 to 13 days	50 to 55 degrees F	9	Direct seed into containers.
Portulaca	Early April	6 to 13 days	65 degrees F	10	Needs light to germinate.
Salvia	Early March	12 to 14 days	60 degrees F	9 to 11	Needs light to germinate.
Snapdragon	Early March	7 to 13 days	45 to 50 degrees F	10	Needs light. Grow cool.
Torenia	Mid-Feb	10 to 19 days	55 to 60 degrees F	10 to12	Needs light to germinate.
Verbena	Early March	12 to 22 days	55 to 60 degrees F	10	Chill seeds before sowing.
Vinca	Early toMid-March	10 to 17 days	65 to 68 degrees F	12 to 13	Grow in warm temperatures.
Zinnia	Mid-April	5 to 9 days	60 degrees F	6 to 7	Direct seed into final container.

The Kansas Vegetable Garden Calendar below can be found in the Kansas Garden Guide from K-State Research and Extension and is a very helpful tool to figure out when crops are generally planted in the garden and harvested.