Cilantro (Coriandrum sativum) is a staple herb of many global cuisines. As with most culinary herbs, fresh cilantro from the garden is leaps and bounds above anything you’ll probably find in your local grocery store. And, lucky for us, it’s straightforward to grow!

Cilantro isn’t the only thing you can harvest from this little plant. It also produces coriander seeds, which are quite popular in Asian and Middle Eastern dishes. 

In this article, I’ll cover all of the cilantro plant growth stages and give you some expert tips for growing the best cilantro or coriander possible. 

Conditions for Growing Cilantro

This annual herb grows well in nearly all climates. You can grow cilantro outdoors in USDA Zones 2 through 11. However, the time of year cilantro grows best will vary depending on the environment.

Cilantro is a cool-season herb that prefers conditions between 60 and 70°F. It can even survive brief periods below freezing. On the other hand, extreme heat can wreak havoc on a cilantro crop and trigger bolting (premature flower production).

Most cilantro is grown in early spring or fall when temperatures are mild. Gardeners in hot parts of the world should grow cilantro mid-winter to prevent bolting.

Temperature is by far the most critical aspect of growing good cilantro. The herb is fairly tolerant of various soil conditions but prefers slightly acidic, fast-draining soil. Cilantro thrives in full or partial sun — direct afternoon sun can burn the leaves.

Cilantro stands typically less than 2 feet tall and wide, making it a great candidate for small garden beds or containers. This is one of those herbs you can strategically tuck into any gaps in your vegetable garden. 

Cilantro Plant Growth Rate

In most areas, you can expect to start harvesting cilantro leaves as early as 30 to 45 days after planting. The seeds won’t develop and mature for at least 45 to 100 days from sowing.

While cilantro’s growth rate can vary greatly depending on the weather conditions and time of year, it’s normal for the leaves to grow several inches weekly! Cilantro leaves can reach up to 20 inches tall, but most are harvested before they reach that size.

Growth Stages of Cilantro

I’ve covered how cilantro and coriander come from a single plant species. Several unique cultivars are available to home gardeners, but all produce edible leaves and seeds.

You may also come across some other types of cilantro, namely things like Vietnamese coriander and cilantro. Don’t be fooled. These are entirely different plants than the one we’re discussing here!

• Vietnamese coriander (Persicaria odorata) leaves are commonly used in Southeast Asian cuisine. It is not related to ‘true’ cilantro.

• Culantro (Eryngium foetidum) might look like a typo, but it is a herb all its own. It is widely used in Southeast Asia, as well as in Caribbean and Latin American dishes. Culantro is also not a relative of cilantro. 

Despite the confusing naming conventions, neither Vietnamese coriander nor culantro resemble regular cilantro in the garden.

Now, let’s return to our standard garden cilantro and its particular life cycle:

1. Seed Germination

Cilantro is most commonly started from seed sown directly in the garden. (Some gardeners believe transplanting young cilantro plants even contributes to premature flowering.) For cilantro, a soil temperature between 65 and 70°F is ideal.

The seeds also need adequate moisture to begin sprouting. Water within the soil is absorbed through the tough seed coat. Once a cilantro seed imbibes enough moisture, cells within the seed embryo begin rapidly dividing.

Most cilantro seeds sprout within 5 to 10 days with the right growing conditions. Note that cilantro tends to have a low germination rate of around 50%. I recommend ‘over planting’ to ensure you get a large enough crop. You can always thin the seedlings once they emerge!

2. Seedlings

Healthy cilantro seedlings emerge quickly but may not look the way you expect! Each seedling starts life with two specialized leaves called cotyledons. These leaves are long and narrow, contrasting the plants’ frilly mature foliage.

Cotyledons are essential during the early days of growth. You can think of the cotyledons as the ‘yolk’ of the developing cilantro seedling (just don’t put that on your next science exam!). A days-old cilantro plant can’t yet photosynthesize. The cotyledons hold valuable energy that supports the seedling until its first true leaves have formed.

It usually only takes a few days for the first ‘true’ leaf to appear. This leaf will grow between the cotyledons and should resemble the mature foliage of cilantro. More and more leaves will soon follow.

I like to remind new gardeners that cotyledons have a significant but brief job. Once those mature leaves appear, the plant no longer needs the cotyledons. It’s 100% normal for the cotyledons to turn brown and shrivel up at this stage.

3. Vegetative Growth

A few mature leaves are all your cilantro needs to take off running. Growth from this point is rapid and almost exclusively consists of new stems and leaves emerging from the crown. Keep a close eye on the cilantro during this time. The best time to harvest your cilantro is during the vegetative growth phase.

Beneath the soil’s surface, the root system is also expanding. Cilantro has a central taproot covered in much smaller root hairs. 

By the way, that taproot is just as edible as the aromatic foliage! You may have to dig to find recipes that utilize cilantro root, but it’s reportedly quite tasty.

4. Flowering

Cilantro is similar to many other herbs and vegetables because it starts flowering in response to hot, long days. On average, cilantro will flower when there are at least 12 hours of sunlight per day and the temperature is above 85°F. 

Some cultivars are less susceptible to bolting than others. A couple of varieties recommended by the University of Wisconsin include ‘Santo’ and ‘Caribe’. Remember that no cilantro plant can tolerate prolonged heat without bolting.

Cilantro flowers are generally white (often with a slight pink or purple tinge) and develop in small umbels. Each umbel is made up of several individual florets. Every floret has an ovary that can produce a seed.

5. Seed Production

To produce seeds, the cilantro florets must first be pollinated. Since the flowers are small, common pollinators include tiny syphid flies, gnats, and certain bee species. 

Cilantro is self-fertile, which means you only need one plant to produce coriander seed. The seeds develop quickly after pollination. Many cilantro plants will bear seed just 45 days after being planted in the garden.

When to Harvest Cilantro

You can start harvesting cilantro leaves when the plant is at least 6 inches tall. I recommend pinching off just a few leaves as needed early on. The cilantro will continue producing new leaves for a larger, later harvest.

When you need a large bunch of cilantro (or if the season is coming to an end), take a pair of pruning shears and cut what you need. Be sure to leave some plants intact to collect coriander seeds.

If you want to harvest the seeds for coriander, you’ll need to wait until the cilantro goes to flower. Coriander seeds can be harvested when young and green or dry and brown. 

Green coriander seeds must be hand-picked from the garden. Brown coriander seeds are a bit easier to collect. Cut off the dry seed heads and hang them upside-down, covered in a paper bag. When the seeds are ready, they will drop from the seed heads and land in the bag. 

If you have enjoyed this article, here’s a link to Dill Companion Plants that you may also enjoy.

FAQs Growing Cilantro

Will cilantro keep growing after harvest?

Follow these tips to keep your cilantro growing after harvest. Remove no more than one-third of the plant at one time so that the cilantro has the energy to produce new growth. Harvest the largest, outermost leaves first. Cut cilantro leaves above 1 inch above the soil’s surface.

Does cilantro prefer sun or shade?

Your cilantro will grow best if it receives morning sun and afternoon shade. This herb needs at least 4 hours of sun daily, but harsh, direct sunlight can burn the leaves. Too much sun can also trigger bolting or premature flowering, impacting the herb’s flavor.

Citations

• University of Wisconsin Heat-tolerant cilantro cultivars