How to Easily Grow Cilantro in Water In 30 Days

Do you want to cultivate herbs but not get your hands dirty with soil? Then cilantro is just the perfect herb for you to grow in water within a month! 

For those not aware, cilantro and coriander come from the same plant. Cilantro typically refers to the stems and leaves, while coriander refers to the seeds. You can obtain cilantro/coriander seeds at a garden center, a nursery store, or even your local grocery store.

Here’s how you can get started:

(As an Amazon Associate, I earn from qualifying purchases.)

1. Gently break coriander seeds in half to release them from the husk

This is not always a necessary step, as you can directly grow the seeds as is. The source responsible for developing into cilantro is encased in a hard brown layer called the husk. There are usually two seeds within each husk, so releasing them earlier on aids in accelerating the germination process.

You can use anything from a mortar and pestle, a rolling pin, or even a wooden spatula to crush the husk open and release the seeds. Be gentle in this process as you don’t want them to turn into powder; that’s a different recipe altogether. Once this is done, collect and set aside the husk and true seeds. Feel free to pick out each tiny husk; otherwise, leaving them in is fine. I’ll be over here watching paint dry on the walls. 

2. Sprinkle coriander seeds in a colander suspended over a bucket/bowl of water

Prepare the following items: (Note: The following links are Amazon links)

• A colander, preferably one you don’t intend on using anymore. No, not the stainless-steel kind but the cheap plastic one.
• A small bucket or large bowl with an opening that your colander can comfortably suspend over. Ensure that it is not a transparent bucket or bowl to prevent algae growth from sun exposure.
• Your halved coriander seeds
• Tissue paper
• A spray bottle with water

Here’s how to grow your cilantro:

1. Place the colander over your bucket/bowl.

2. Fill the bucket/bowl with water until it is barely touching the bottom of the colander. Ensure the colander’s base isn’t flooded with water, as this is where the seeds will grow. Leave a 0.5-inch gap between the water’s surface and the colander’s bottom.

Important note on water: use distilled or filtered water. Some areas may have tap water with loads of minerals in it. When this accumulates, it will form salt crusts as the water evaporates. Too much of this will harm the herb’s growth.

3. Sprinkle your seeds all over the bottom of the colander. 

Optional: If the holes in your colander are larger than your coriander seeds, place a damp sheet of tissue paper at the bottom first to keep the seeds from falling through. Alternatively, you can get a colander with smaller holes instead.

4. Place another sheet of tissue paper over the seeds.

5. Spritz the tissue paper with water to ensure it is damp and weighed down to cover the seeds. Do this daily, possibly twice a day, so the seeds won’t dry out.

3. Place the coriander seeds in an area with 6 hours of full sun

This bit can be tricky because too much sunlight may scorch the herb’s leaves or force the plant to bolt early. ‘Bolting’ is defined as the process when leafy greens begin to produce flowering stalks, causing the leaves to turn bitter. This often happens in warmer climates where the herbs are encouraged to multiply and seed in the heat. But since we’re trying to develop cilantro quickly, more sun time is the answer.

If you live in warm climates, I recommend placing your cilantro in a bright but shaded area. This way, you can prevent the leaves from burning. However, keep an eye on your sprouts as they may grow faster but also bolt quicker. Cilantro will taste bitter once it has bolted, so you want to harvest your herb before that happens.

If you live in cool climates, it’s relatively safe to keep your herbs under full sun longer. But again, exercise caution and move your cilantro to a shaded area if its leaves look scorched.

If you’re growing this indoors, a windowsill is a good place to start with. For outdoors, make sure it is in a cool, shaded, and protected area where animals won’t try to gobble up your sprouts.

4. Change the water in the bucket/bowl every 2-3 days

Apart from checking whether the seeds have started sprouting, you need to change the water in the bucket/bowl every 2-3 days, so it’s constantly fresh for the growing herb. 

If there’s a color change in the water, you definitely need to change it. It may be caused by algae or bacterial growth, but it’s typically hard to gauge. So err on the side of caution, rinse your bucket/bowl thoroughly with soapy water and top it off with clean filtered/distilled water. You don’t want whatever was growing in the dirty water to latch onto your cilantro and cause stomach aches come harvest time. 

Once the roots have sprouted, ensure they are only half-submerged in water. Despite the simple hydroponics setup it’s growing in, it still needs oxygen to develop well. Adjust the water level accordingly in the bucket/bowl to prevent the roots from drowning in the water.

Important note on fertilizers: It’s not completely necessary. But you can add liquid fertilizer into the water for the plant to get extra nutrients. The added nutrients are an excellent boost to their development. Still, ensure to only put half the recommended dose as per the product’s instructions. Too much fertilizer will still kill your herbs.

5. Harvest the cilantro as soon as it is 5-6 inches tall

You can start harvesting your cilantro in about 30 days or less once it has reached its observed height. Here are 3 ways you can collect them:

1. Cut ⅓ of the collective herb from the external/outer portion of the crop. This way, you can get a continual harvest from the plant a few times. Slowly work your way inwards to the center of the plant before it starts to bolt. 
2. Pluck the top parts of the leaves individually, however many you need/want. This encourages the plant to develop more leaves, which you can keep coming back to for harvest.
3. Harvest the whole herb. Bunch them together using a rubber band and cut them 1-2 inches from the colander’s base.

You can also let the herb bolt and seed. This way, you can collect the coriander seeds for growing more cilantro later on. Note: the seed won’t give you the same exact herb as you originally started with, so there may be a slight change in taste or growth. 

A good tip for keeping cilantro fresh for longer is freezing them, but only if its to be cooked. If you intend to use the herb as a garnish, store them in an airtight container with tissue paper to keep them crisp and set them aside in the fridge.

When you start the growing process again from scratch, make sure to rinse, scrub, and sanitize the items used before. Pair that with your collected coriander seeds from the previous cilantro batch, and you’re good to go! All in all, that’s everything you need to know about growing cilantro in water.

References:
https://hgic.clemson.edu/factsheet/herbs/

https://extension.uga.edu/publications/detail.html?number=B1170

https://extension.unr.edu/publication.aspx?PubID=2756

https://extension.okstate.edu/fact-sheets/hydroponics.html

https://extension.illinois.edu/blogs/good-growing/2017-09-07-home-hydroponics

https://extension.umn.edu/how/small-scale-hydroponics#sources-2645960