How long does hydroponics take to grow a harvest? Radishes and mustard greens can be ready in about 3 to 6 weeks from seed, leaf lettuce and arugula in about 6 to 7 weeks, herbs in 7 to 10 weeks, and tomatoes or peppers about 11 to 12 weeks after transplanting. The variety, light, temperature and nutrition decide where in each range your crop lands.
| Crop group | Typical days to first harvest | Example crops |
|---|---|---|
| Fastest greens | 20–50 days from seed | Radish, mustard, leaf lettuce, arugula, kale |
| Herbs | 40–75 days from seed | Dill, cilantro, basil, parsley |
| Small fruiting and root crops | 50–65 days from seed | Bush beans, zucchini, peas, beets, cucumbers |
| Heading crops | 55–80 days from transplant | Head lettuce, broccoli, cauliflower |
| Long fruiting crops | 75–95 days from transplant | Tomatoes, peppers, eggplant |
How Long Does Hydroponics Take to Grow Each Crop?
The chart below answers “how long does hydroponics take to grow?” for 25 common crops, using the days-to-harvest ranges published by NC State Extension for home vegetable gardens. They are a fair baseline for hydroponics too, because a crop’s days to maturity are set mostly by its genetics. “From seed” means from sowing; “from transplant” means from moving a seedling into the system.
| Crop | Days to harvest | HydroponicEra guide |
|---|---|---|
| Radish | 20–25 from seed | Radish |
| Mustard greens | 30–40 from seed | Mustard greens |
| Leaf lettuce | 40–50 from seed; 15–25 from transplant | Lettuce |
| Arugula | 40–50 from seed | Arugula |
| Kale | 40–50 from seed; 14–22 from transplant | Kale |
| Dill | 40–55 from seed | Dill |
| Bok choy | 45–90 from seed; 30–75 from transplant | Bok choy |
| Cilantro | 50–55 from seed | Cilantro |
| Spinach | 50–60 from seed | Spinach |
| Kohlrabi | 50–60 from seed | Kohlrabi |
| Basil | 50–75 from seed; 14–35 from transplant | Basil |
| Bush snap beans | 50–55 from seed | Beans |
| Zucchini (summer squash) | 50–60 from seed; 30–40 from transplant | Zucchini |
| Bush peas | 54–60 from seed | Peas |
| Beets | 55–60 from seed | Beets |
| Cucumbers | 56–65 from seed; 28–37 from transplant | Cucumbers |
| Swiss chard | 60–70 from seed; 32–42 from transplant | Swiss chard |
| Green onions | 60–70 from seed; 42–56 from transplant | Green onions |
| Head lettuce | 70–85 from seed; 45–60 from transplant | Lettuce |
| Parsley | About 75 from seed; about 33 from transplant | Parsley |
| Broccoli | 70–80 from transplant | Broccoli |
| Cauliflower | 85–95 from seed; 55–65 from transplant | Cauliflower |
| Tomatoes | 75–85 from transplant (125–135 from seed) | Tomatoes |
| Peppers | 75–80 from transplant (145–150 from seed) | Peppers |
| Eggplant | 90–95 from transplant | Eggplant |
For the fastest answer to “how long does hydroponics take to grow?”, look at microgreens. They are cut at the seedling stage, so they are faster than anything on this chart. See our microgreens guide.
Is Hydroponics Faster Than Soil?
Sometimes, but not by magic. The honest answer to how long does hydroponics take to grow compared with soil is “about the same clock, with fewer setbacks.” Hydroponics doesn’t rewrite a variety’s days to maturity. What it can do is remove common soil stresses: dry spells, uneven nutrients and root competition. Leafy greens grown with steady light, warm (not hot) water and a balanced nutrient solution often land at the short end of the range. Fruiting crops are limited mostly by light, temperature and pollination, so a weak grow light slows them down no matter how good the water is. Our hydroponics vs soil comparison covers the trade-offs.
How Do You Read Days to Maturity on a Seed Packet?
Seed packets and US seed catalogs list “days to maturity,” but the clock doesn’t always start at sowing. For crops normally sown directly, such as radishes, beans and leaf lettuce, the count usually begins at sowing. For crops normally started indoors and transplanted, such as tomatoes, peppers and eggplant, it usually begins at transplanting. That is why a tomato labeled “75 days” can still take about four months from seed. When you ask how long does hydroponics take to grow a specific variety, start with the packet number, then add seedling time if the count starts at transplant.
Packets also assume outdoor summer conditions. Indoors, your light level replaces the sun, so a dim setup will run behind the packet and a strong, well-tuned light can keep pace with it.
What Changes How Long Hydroponics Takes to Grow?
- Light. Daily light integral (DLI) is the biggest lever indoors. Low light means slow, leggy plants. See PPFD and DLI.
- Temperature. Cool-season greens slow down in the cold and bolt in the heat. Warm-season crops stall below their comfort range. See reservoir temperature.
- Nutrition and pH. An EC or pH that drifts out of range can stall growth for days. See EC and TDS.
- Variety. A “baby leaf” lettuce and a large romaine are on very different clocks. Check the seed packet’s days to maturity, because any answer to how long does hydroponics take to grow starts with the variety.
- Start method. Transplants skip the seedling weeks. Seeds sown directly in the system start the clock at zero. See germination methods.
How Do You Plan Harvests Using These Times?
- Pick your target date. Decide when you want to eat, then use the chart above to see how long does hydroponics take to grow each crop. Count back the days to harvest for each crop.
- Add seedling time. If the chart gives “from transplant,” start seeds earlier so seedlings are ready on schedule.
- Stagger sowings. Sow lettuce and herbs every 2 to 3 weeks for a steady supply. See continuous harvest planning.
- Harvest outer leaves early. Many greens can be picked as baby leaves before full maturity.
- Log real dates. Your own records beat any chart. Use a simple grow log.
What Mistakes Slow Hydroponic Crops Down?
| Mistake | Effect on timing | Fix |
|---|---|---|
| Weak light for fruiting crops | Slow flowering, few fruits | Upgrade light or grow greens instead |
| Reservoir too warm | Root problems that stall growth | Keep the water cool and oxygenated |
| pH drift | Locked-out nutrients, pale growth | Check pH every day or two |
| Wrong season variety | Early bolting or slow heading | Choose varieties bred for indoor growing |
| Comparing to the wrong clock | Feeling “behind” schedule | Check whether a date is from seed or transplant |
FAQs: How Long Does Hydroponics Take to Grow?
What grows fastest in hydroponics?
Microgreens, then radishes, mustard greens and leaf lettuce.
How long does hydroponics take to grow lettuce?
Leaf lettuce takes about 40 to 50 days from seed, or 15 to 25 days after transplanting a seedling, based on NC State Extension’s ranges.
How long does hydroponics take to grow tomatoes?
About 75 to 85 days after transplanting, or roughly four months from seed.
How long does hydroponics take to grow herbs?
Basil, cilantro and dill usually take about 7 to 10 weeks from seed, and you can harvest sprigs before then.
How long does hydroponics take to grow from seed to harvest?
Roughly 6 to 7 weeks for leaf lettuce and arugula, 7 to 10 weeks for most herbs, and about 4 to 5 months from seed for tomatoes and peppers, based on NC State Extension’s ranges.
Does hydroponics grow plants twice as fast?
Not reliably. Results vary with light, temperature, crop and variety. Expect a steady, predictable harvest rather than a guaranteed speed-up.
Related HydroponicEra Guides
Sources
- NC State Extension — Central North Carolina Planting Calendar for Annual Vegetables, Fruits, and Herbs
- University of Florida IFAS — Hydroponic Systems for Home Gardeners (HS1279)
- University of Minnesota Extension — Growing Lettuce, Endive and Radicchio in Home Gardens