Sources and credits

Sources

• How to sow seeds indoors, Royal Horticultural Society
• Hardening off tender plants, Royal Horticultural Society
• Damping off, Royal Horticultural Society
• Vegetable seeds: sowing guide, Royal Horticultural Society
• Harvested seed germination requirements (PDF), Royal Horticultural Society
• Starting seeds indoors, Clemson Cooperative Extension (HGIC)
• FAQs about starting vegetable seeds indoors, Clemson Cooperative Extension (HGIC)
• Make your own seed-starting mix, Oregon State University Extension
• Safeguard your seedlings from damping-off, Penn State Extension
• Sowing annual seeds, Penn State Extension
• How to prevent seedling damping off, University of Minnesota Extension
• Growing cucumbers in home gardens, University of Minnesota Extension
• Growing parsley in home gardens, University of Minnesota Extension
• Seed saving: vegetables (PDF), University of Maryland Extension
• Saving garden seeds (PDF), Montana State University Extension
• Saving seeds from your garden (The Real Dirt), University of California Cooperative Extension

Sowing depth for larger seed (two to three seed widths), the hardy-crop plant-out offset in the planner, and notes on individual crops are general gardening practice, flagged as such where they appear. Always follow your seed packet.

Pictures

• 5670Farm Ready Seedling Facility East West Seed Philippines 20 by Judgefloro, CC0, via Wikimedia Commons.
• Pepper and tomato seedling trays at Boğaziçi University 2026 by Furkan Akkurt, CC BY-SA 4.0, via Wikimedia Commons.
• Cucumber seedlings 4 by Pascal Kings, CC BY 4.0, via Wikimedia Commons.
• Broad bean in a small pot by Seanbhean-chríonna-caite, CC0, via Wikimedia Commons.
• Germinating Beans by Geossegawa, CC BY 4.0, via Wikimedia Commons.
• Onions in the greenhouse (5630796833) by Dwight Sipler from Stow, MA, USA, CC BY 2.0, via Wikimedia Commons.
• Temple Sowerby, Acorn Bank, Mizuna and lettuce seedlings - geograph.org.uk - 7625183 by Michael Garlick, CC BY-SA 2.0, via Wikimedia Commons.