| Days to Maturity | Estimated days from germination or transplant to harvest |
| Planting Depth | Distance below soil surface to place the seed |
| Seed/Plant Spacing | Required distance between seeds and between thinned seedlings |
| Sun Requirements | Full sun (6+ hrs), Part sun (3–6 hrs), Full shade (<3 hrs) |
| USDA Hardiness Zone | Zone range in which a perennial plant can survive winter (USDA Agricultural Research Service) |
| Indoor Start Date | Weeks before last frost to start seeds indoors |
| Seed Type | Open-pollinated, Heirloom, or Hybrid (F1) |
What You'll Find on a Standard Seed Packet
Seed packets are designed to be small, but they carry a surprising amount of practical information. Understanding each element lets you plant at the right time, in the right place, and at the right depth — which is most of what separates a successful garden from a frustrating one. Before you put anything in the ground, make sure you're working through a spring garden prep checklist so conditions are ready to receive seeds.
| Days to Maturity | Estimated days from germination or transplant to harvest |
| Planting Depth | Distance below soil surface to place the seed |
| Seed/Plant Spacing | Required distance between seeds and between thinned seedlings |
| Sun Requirements | Full sun (6+ hrs), Part sun (3–6 hrs), Full shade (<3 hrs) |
| USDA Hardiness Zone | Zone range in which a perennial plant can survive winter (USDA Agricultural Research Service) |
| Indoor Start Date | Weeks before last frost to start seeds indoors |
| Seed Type | Open-pollinated, Heirloom, or Hybrid (F1) |
The sections below explain what each label term means in plain language, so you can decode any packet you pick up.
Days to Maturity
Days to maturity tells you approximately how many days a plant needs — from germination or transplant — to produce a harvestable crop. It is an estimate, not a guarantee; your local temperatures, soil quality, and sunlight hours all influence the actual timeline.
For transplants (like tomatoes or peppers), the count typically starts from the day you set seedlings in the ground, not from when you first sow seeds indoors. For direct-sown crops (like carrots or beans), it usually starts from germination. Check the packet language carefully — it will often specify which applies.
Use days-to-maturity to work backward from your first expected frost date. If a crop needs 80 days and your first frost arrives in late October, count back 80 days from that date to find your latest safe planting window.
Planting Depth and Spacing
Planting depth tells you how far below the soil surface to place a seed. A common rule of thumb in gardening is to plant a seed about two to three times as deep as the seed is wide. Packets usually express this in fractions of an inch (e.g., ¼ inch, ½ inch, 1 inch). Planting too deep can prevent germination; too shallow and the seed may dry out. If you're having trouble getting seeds to sprout, depth is one of the first things to check — see our guide on why seeds aren't germinating for a fuller breakdown.
Spacing appears in two forms on many packets:
- Seed spacing (or sow spacing): How far apart to place individual seeds when sowing.
- Plant spacing (or thin to): How far apart seedlings should stand once thinned. Crowded plants compete for water, nutrients, and light, so thinning is not optional.
Row spacing is sometimes listed separately for gardeners growing in traditional rows rather than raised beds or intensive plots.
Days to Maturity
The approximate number of days from germination or transplanting until a crop is ready to harvest. Actual timing varies by climate and growing conditions.
Direct Sow
Planting seeds directly into outdoor garden soil rather than starting them indoors. Many root vegetables and fast-growing crops prefer direct sowing.
Thinning
Removing excess seedlings after germination so that remaining plants have enough space, light, and nutrients to grow properly.
Open-Pollinated
Seeds pollinated naturally by wind, insects, or other means. Plants grown from open-pollinated seed produce offspring with consistent traits, making seed saving reliable.
Hybrid (F1)
A seed bred from two distinct parent varieties to produce specific traits such as disease resistance or uniform size. Seeds saved from hybrids will not reliably replicate the parent plant.
Hardiness Zone
A geographic designation from the USDA Plant Hardiness Zone Map indicating the average annual minimum winter temperature in a region, used to determine which perennial plants can survive locally.
Sun Requirements, USDA Zones, and Other Key Details
Sun requirements are usually listed as one of three categories:
- Full sun: 6 or more hours of direct sunlight per day.
- Part sun / Part shade: 3–6 hours of direct sunlight.
- Full shade: fewer than 3 hours of direct sunlight.
USDA Hardiness Zones appear on packets for perennials and some biennials — plants you expect to return year after year. The USDA Plant Hardiness Zone Map divides the U.S. into 13 zones based on average annual minimum winter temperatures. If a perennial packet says "Hardy in Zones 5–9," it means the plant can survive winters in those zones without special protection. Annual vegetables don't typically carry zone information because they complete their life cycle in one season. For a full explanation of how zones work, see our article on understanding USDA plant hardiness zones.
Indoor start date (sometimes labeled "Start Indoors") tells you how many weeks before your last frost date to sow seeds inside. This is especially common for slow-maturing crops like peppers, eggplant, and certain herbs.
Open-pollinated, heirloom, and hybrid are seed-type labels worth noting. Open-pollinated seeds produce plants whose seeds can be saved and replanted. Heirloom varieties are open-pollinated cultivars with a long history. Hybrid seeds (labeled F1) are bred for specific traits; seeds saved from hybrids will not reliably produce the same plant. None of these terms indicates superior quality — they reflect breeding method and seed-saving potential.
Ready to put this knowledge to work? Our guide to starting a vegetable garden from scratch walks you through every step from site selection to harvest.