How to Grow Cilantro From Seed Indoors (Winter Is the Easy Season)

Nov 5, 2026
Basil, cilantro and chives growing together in a copper Buzzy windowsill planter on a kitchen counter

Most herb advice treats winter as the hard season. For cilantro, that gets it backwards.

If you want to know how to grow cilantro from seed and you have been putting it off until spring, here is the good news. A cool, bright windowsill in January is closer to what this plant actually wants than a hot one in July. Cilantro is a cool-season annual. Heat is what ruins it.

There is one catch, and it involves your grow light. We will get to that, because the standard indoor herb advice was not written with cilantro's one quirk in mind.

Why does cilantro do better in winter?

Two reasons, and they both point the same way.

The first is temperature. Cilantro runs to flower when it gets hot, which growers call bolting. Once it starts, the leaves stop coming. Texas A&M AgriLife puts the trigger above about 85°F. Oregon State University Extension puts it a little lower, above about 80°F. Utah State University Extension tells indoor growers to keep the growing medium below 75°F for the same reason. A kitchen windowsill in winter sits comfortably under all three numbers.

The second reason is day length, and it is the one almost nobody mentions. Cilantro flowers faster when the days get long. Floriculture research from Michigan State University, reported in Produce Grower, found that a day of 13 hours or more pushes it toward flowering. Holding it at 12 hours or less delays that. A published trial shows how far the effect reaches. Plants on 16-hour days formed flower buds at 49 days. Plants on 8-hour days took 73. Nobody gets an 8-hour day on a windowsill. It does show which way a shorter day pushes the plant.

Across most of the US, natural daylight from January through March runs somewhere between nine and twelve hours. Cool room, short days. Both of the things that make cilantro bolt are turned down at once.

How long does cilantro take to sprout?

Longer than basil, and that surprises people.

These numbers come from our own kit instructions, so they match the packet in your box.

Step What to expect
Planting depth A quarter inch, lightly covered
Sprouting time 14 to 21 days
Warmth for sprouting 65 to 70°F
Light Full to partial sun
First leaves worth picking Around 4 to 6 weeks
Full maturity 60 to 75 days
Height at full size 18 to 24 inches, picked long before that

Two to three weeks of nothing is normal. Utah State University Extension gives about 21 days. The Royal Horticultural Society says one to three weeks outdoors and two to three weeks for pots indoors. UC Marin Master Gardeners have seen it take 25. An empty-looking pot on day ten is right on schedule.

One useful trick for the sprouting stage. Give the pot warmth first, then move it to the cool bright spot once the seedlings are up. Oregon State records cilantro sprouting from 55°F upward, so a cool room only slows it down. Warm to start, cool to grow.

Buzzy culinary herb grow kit contents for growing cilantro from seed: copper planter, two growing medium pellets and a seed packet
The two discs are compressed growing medium. They go into two and a quarter cups of water and expand into enough to fill the planter.

Why cilantro seeds come two to a husk

Pick up a cilantro seed and look closely. That little round, ridged ball is a husk, and there are usually two seeds inside it.

Michigan State University Extension describes the structure and the fix in one line. Roll the husks between your palms to crack them open and free the seeds. Wisconsin Horticulture says the same thing. You do not have to do this, and plenty of people sow the husks whole. It does help the seeds meet water sooner.

Skip the overnight soak you may have read about. The extension advice behind that is aimed at Florida growers dealing with warm nights, not at a January windowsill.

The grow light mistake that makes cilantro bolt

This is the one piece of standard herb advice to set aside.

Standard indoor herb advice says to run a grow light 12 to 16 hours a day. Iowa State, Illinois and UC Santa Clara Master Gardeners all give a version of that number, and for basil or chives it is good advice.

For cilantro it works against you. A 16-hour day is exactly the long day that tells this plant to stop making leaves and start making flowers.

The fix is simple once you see it. Cilantro needs more light intensity, not more light hours. So put the lamp closer, roughly 6 to 12 inches above the leaves, and keep the timer at about 10 to 12 hours a day. You get a brighter plant without handing it the long-day signal.

If you are going by daylight alone, you do not have this problem at all in winter. The sun is already giving you a short day.

Is a windowsill bright enough?

Cool is only half the claim. Bright is doing just as much work.

University of Illinois Extension calls light the most limiting factor for growing anything indoors. UC Sonoma Master Gardeners put a number on the floor: under about six hours of sun a day, herbs go lax and leggy. The Royal Horticultural Society says windowsill cilantro turns pale in low light.

So pick the brightest window you have. South-facing is best, east or west will do. A dim north window in January will not carry it, however cool the room is.

Two small things that help. Turn the pot a quarter turn every few days, since low winter sun comes in at a sharp angle. And keep the planter off the radiator. Containers dry out fast, and a hot dry pot is the quickest way to make cilantro bolt in the middle of winter.

Basil, cilantro and chives grown from seed in a copper windowsill planter at around two months
Cilantro is the fan-shaped one in the middle. This is roughly the two-month stage, not the two-week stage.

When can you start picking cilantro?

Earlier than the maturity date suggests, which is the nice part.

Sixty to seventy-five days is the time to a fully mature plant. You do not have to wait that long to eat. UC Marin Master Gardeners say you can take outer leaves about a month after sowing, once the plant is around six inches tall. Penn State Extension lists some varieties as ready for leaf picking in 28 to 50 days.

How you pick matters more than when. Take the outer leaves and leave the middle alone, because new growth comes up from the center of the plant. UC Marin spells that out, and Wisconsin Horticulture adds that removing the older outer leaves encourages new ones.

Give it a couple of weeks between pickings and you can take several light harvests from one sowing. Cutting the whole plant back at once also works, and Iowa State University Extension says annual herbs take that fine. You just get fewer rounds out of it.

Why does cilantro stop producing?

Because of what it is. Cilantro has one growing point in the middle, and once that point switches over to a flower stalk, the leaf supply is finished.

Cilantro is an annual. Mint and chives are perennials, which is why they come back year after year from the same roots. Michigan State University Extension describes the cilantro sequence plainly: the plant bolts, flowers, sets seed and finishes its life.

Iowa State University Extension gives the practical rule for herbs grown indoors. Cut annual herbs back fairly hard, leaving four to six inches of stem, and after several harvests start fresh plants from seed. That is the whole plan for cilantro.

How often should you sow again?

Every two to three weeks is the answer most extension services land on.

Wisconsin Horticulture and UC Santa Clara both suggest two to three weeks. Penn State says two to four. Texas A&M says weekly, though that is written for a field, not for one planter on a sill.

For a windowsill, here is the version that fits real life. Sow one section. Three weeks later, sow the next section. By the time the first one is finished, the second one is ready to pick. Our Culinary Herb planter is divided into sections for exactly this kind of staggering.

Taco Night grow kit contents with tomato and cilantro seed packets, yellow planter and growing medium
Two packets, one planter. Keep the tomato at one end and the cilantro at the other, so you can cut one side back without disturbing the other.

Cilantro or coriander?

Same plant, different parts.

University of Illinois Extension puts it as neatly as anyone. Harvest the leaves and it is cilantro. Harvest the seeds and it is coriander. Clemson Cooperative Extension makes the same point about the herb and the spice coming from one plant.

Which makes bolting a swap rather than a loss. The leaves turn bitter once flowering starts, and Clemson notes that is when the seeds form as the plant finishes its life. Oregon State says seed follows roughly four to six weeks after flowering. Wisconsin puts it at two to three weeks after the flowers appear, depending on conditions.

So if your plant goes up instead of out, let it. Wait for the husks to turn light brown, roll them in your hand, and you have your own coriander for the spice jar.

Which kit to start with

Cilantro is in four of our windowsill kits, and the choice mostly comes down to what you want beside it.

Cilantro with basil and chives. The Organic Culinary Herb Grow Kit in the copper planter, or the same three in the galvanized Kitchen Herbs planter. Worth knowing: basil wants 70°F and full sun, so give the basil end the brighter, warmer side of the sill.

Cilantro with tomato. The Taco Night kit, in yellow or galvanized. Both seeds go in a quarter inch deep, which makes planting day simple. The tomato is the slower half at 80 to 96 days.

Tomato and cilantro grown from seed together in a yellow Buzzy windowsill planter
Tomato on the left, cilantro on the right. The tomato will still be working long after you have cut the cilantro twice.

The rest of the range is in our herb grow kits and culinary grow kits collections.

How to grow cilantro from seed: the short version

Sow a quarter inch deep. Keep it warm for the two to three weeks it takes to come up. Then move it to the brightest cool window in the house and leave the lamp timer at 10 to 12 hours. Pick the outer leaves from about week four to six. Sow again three weeks later.

Do that between January and March and one sowing should give you several light harvests, starting around week four to six. That is the stretch of the year when cilantro is easiest to keep happy.

Keep reading: How to Grow Basil from Seed · How to Grow Mint Indoors From Seed · Growing Seeds Indoors in Winter · Your Herb Garden Doesn't Have To Wind Down

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