Invictus Urban Farms

Guide

Days to maturity: seed-to-harvest times, crop by crop

"Days to maturity" on a seed packet doesn't always start counting from seed. Here's the number both ways, plus how often to re-sow to keep a small space producing.

The counting trick to know first

Seed catalogs count days to maturity from whichever start the crop is normally given. Direct-sown crops — radishes, carrots, beans, lettuce — count from the day seed hits soil. Transplanted crops — tomatoes, peppers, eggplant, broccoli — count from the day a six-to-eight-week-old seedling goes into its final pot. That's why a "70-day" tomato and a "60-day" carrot are nowhere near each other in real elapsed time: the tomato's clock started with a two-month head start. The chart below spells out both columns so the comparison is honest.

The chart

CropFrom seedFrom transplantSuccession interval
Radish22–30 days7–10 days
Arugula21–40 days7–14 days
Lettuce, baby leaf28–35 days10–14 days
Lettuce, full head45–60 days30–40 days10–14 days
Spinach35–45 days10–14 days
Green onion60–70 days14–21 days
Beet50–60 days14–21 days
Carrot60–80 days14–21 days
Turnip40–55 days14–21 days
Bush beans50–60 days14–21 days
Peas55–70 daysSingle spring + fall sowing
Kale55–65 days40–50 daysCut-and-come-again instead
Swiss chard50–60 days35–45 daysCut-and-come-again instead
Zucchini / summer squash45–55 days40–50 daysOne mid-season re-sow
Cucumber50–70 days40–50 daysOne mid-season re-sow
Basil55–70 days25–35 days to first cuttingCut-and-come-again instead
Cilantro45–55 days14–21 days; bolts fast in heat
Tomato100–140 days60–85 days
Pepper110–150 days60–90 days
Eggplant110–140 days65–85 days
Broccoli90–115 days55–70 daysSpring + fall crop
Potato70–120 days from seed piece

Ranges cover normal variety spread — 'Cherry Belle' radishes at 22 days versus 'French Breakfast' closer to 30 — and normal weather. Cool temperatures, short days, and shade all stretch the numbers: the same lettuce takes noticeably longer in a part-shade spot, which is worth pairing with the light floors in our sunlight requirements chart. Heat compresses maturity for warm-season crops and ends it early for cool-season ones by triggering bolting.

Using the succession column

The succession interval is the re-sowing rhythm that keeps harvests continuous instead of arriving as one glut. The logic is simple: sow batch two while batch one is half grown, and by the time you've eaten batch one, batch two is ready. In a small container garden you don't need a new pot per sowing — a single square's worth from our square-foot planting chart per interval is plenty for one or two people, and radishes and baby lettuce can be re-sown into the gap left by the plants you just pulled.

Crops marked "cut-and-come-again" — chard, kale, basil, leaf lettuce handled loosely — don't need succession at all: harvest the outer leaves, leave the growing center, and one planting produces for months. Fruiting crops don't need it either, because a single tomato or pepper plant is itself a continuous harvest from first fruit to frost.

Counting backward for a fall crop

The same numbers run in reverse at the end of the season. Take your area's average first-frost date, subtract the crop's days to maturity, then subtract another two weeks — the "fall factor" that accounts for shortening days slowing growth — and you have the last sensible sowing date. A 30-day radish can go in five to six weeks before frost; a 60-day carrot needs to be in the ground by late July in most cold-winter climates. Cool-season greens are the exception worth pushing: lettuce and spinach tolerate light frost, so their last sowing can run right up to a month before the frost date, and they often taste better for the cold.

Days-to-maturity figures are the typical catalog ranges for common varieties, to first harvest rather than final size. Your seed packet's number beats this table for the specific variety in your hand; the table is for planning before packets are bought.