Seed Saving Desk: which seeds to save and how

Pick what you grew and the desk tells you if the seed will come true, when it is ready, and how to clean and dry it. Check which squash and pumpkins could have crossed, then log your seed jar with a test-by year. Your list saves on your device. No account needed.

Free seed saving planner. See which garden seeds come true, how far apart varieties must be, when seed is ready, and how to ferment, dry, and store it. Includes a squash and pumpkin cross check and a seed jar log.

Start with open-pollinated plants

Seed from open-pollinated and heirloom varieties grows into plants like the parent. Seed from F1 hybrids grows, but the plants are a new mix of traits. Tomatoes, peppers, beans, peas, and lettuce are the easiest seeds to save because their flowers pollinate themselves.

Seed saving chart

Crop	Level	Pollination	Distance for pure seed	Method	Ready when
Tomato	Easy	Self	25 to 100 ft	Ferment	Fully ripe fruit
Pepper	Easy	Self and insects	160 to 500 ft	Dry	Fully ripe and starting to wrinkle
Eggplant	Easy	Self	150 ft	Wet	Past eating stage, skin dull and hard
Bean	Easy	Self	10 to 100 ft	Dry	Pods brown and rattling
Pea	Easy	Self	50 ft	Dry	Pods brown and rattling
Lettuce	Easy	Self	50 ft	Dry	Flower heads white and fluffy
Cucumber	Takes care	Insects	1,600 ft	Ferment	Fruit yellow or orange, weeks past eating
Squash and zucchini	Takes care	Insects	1/2 to 1 mile, same species	Wet	Rind hard; winter squash stored until it softens
Pumpkin	Takes care	Insects	1/2 to 1 mile, same species	Wet	Fully mature with a hard rind
Melon	Takes care	Insects	1/2 to 1 mile	Wet	1 to 2 weeks past ripe
Watermelon	Takes care	Insects	1/2 to 1 mile	Wet	Fully ripe, seeds dark and hard
Sweet corn	Advanced	Wind	1/2 mile	Dry	Husks brown, kernels hard
Radish	Takes care	Insects	1,500 ft	Dry	Pods brown and dry
Spinach	Advanced	Wind	1/2 mile	Dry	Seed tan and dry
Carrot (second year)	Advanced	Insects	1,500 ft	Dry	Umbels brown
Beet and Swiss chard (second year)	Advanced	Wind	1/2 mile	Dry	Seed clusters brown
Onion and leek (second year)	Advanced	Insects	1,500 ft	Dry	First black seeds show
Kale, cabbage, broccoli, collards	Advanced	Insects	1/2 mile	Dry	Pods tan and dry
Marigold	Easy	Self and insects	Grow one variety	Dry	Heads dry and brown
Zinnia	Easy	Insects	1/4 mile	Dry	Heads and stem below brown
Sunflower	Easy	Insects	Grow one variety	Dry	Back of head yellow to brown
Cosmos	Easy	Insects	Grow one variety	Dry	Seeds dark, before they drop

Distances are home garden figures from UC Master Gardeners, UGA Extension, and SDSU Extension. They prevent most crossing, not all.

Which squash and pumpkins cross

Squash, pumpkins, and gourds cross only within the same species. A cross does not change this year's fruit, only the plants grown from its seed.

Species	Includes
Cucurbita pepo	Zucchini, yellow squash, pattypan, acorn, spaghetti, delicata, pie and jack-o-lantern pumpkins, ornamental gourds
Cucurbita moschata	Butternut, Long Island Cheese, Dickinson, and Cinderella pumpkins
Cucurbita maxima	Hubbard, buttercup, kabocha, turban, giant pumpkins
Cucurbita argyrosperma	Cushaw
Cucumis melo	Cantaloupe, honeydew, muskmelon
Cucumis sativus	Cucumber
Citrullus lanatus	Watermelon

Dry and store

Dry seed until it snaps instead of bending. Store it in a sealed glass jar, cool and dry. 32 to 41F is ideal, so the refrigerator works. A packet of silica gel or 1 to 2 tablespoons of powdered milk wrapped in a tissue keeps the jar dry. Label each packet with the crop, variety, and year, and plant it the next season for the best germination.

Guides

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