Are you struggling with bolting cilantro plants? Are your plants more spindly and weak than strong and proud?
It has taken me a while and many mistakes to learn how this plant wants to be grown.
To summarize, cilantro does not like heat. Think spring and fall, the shoulder seasons, and you will see stronger plants. Or, read on to learn how to grow cilantro year-round.
Cilantro (Coriandrum sativum) is one of the world’s most popular and used herbs. We grow cilantro from seeds continuously throughout the growing season. Here in this article, we will share our best tips and techniques.
Fun fact 1: Where I live both seed and leaves are known as coriander. But in large parts of the world, the green part of the plant is called cilantro whereas the seed is called coriander.
Cilantro leaves are sometimes confused for flat-leaved parsley, but the distinct smell and taste take care of any risk of mix-ups.
Fun fact 2: Cilantro is also known as Chinese parsley.
- Why is Cilantro Giving Gardeners Problems?
- How to grow cilantro in your garden
- Grow Cilantro Indoors
- Harvest Cilantro For The Seeds
- Summary and key takeaways
Why is Cilantro Giving Gardeners Problems?
Cilantro is a fast-growing annual plant that lends itself to being planted continuously throughout the season.
Still, many gardeners struggle to grow strong plants. From my experience, there are 3 main reasons why people fail:
- Problem with seed starting: Cilantro can be challenging to germinate but is relatively easy to grow from the first leaves sprouting.
- Incorrect harvesting: Harvesting too early, too much, or not often enough. Learn more about harvesting cilantro.
- Wrong timing: You can do everything right and fail if you do not watch the heat.
With this update, I will share how to address each problem and what I have learned over the years.
I start seeds in pots in February / March and then new batches every 2 to 3 weeks. From spring to fall I grow plants outdoors and then move indoors for the winter. If the leaves go yellow due to lack of light, I use LED grow lights.
How to grow cilantro in your garden
You can grow cilantro in pots or sow seeds directly in your herb garden.
Here, it is key to know your weather.
Coriander seeds are somewhat resilient to cold. Still, we always wait for a ground temperature of about 10 degrees Celsius (50 degrees Fahrenheit) before planting seeds in our herb garden.
Planting seeds directly in your herb garden is relatively straightforward.
- Create a line in the ground approximately 1 cm (1/2 inch) deep.
- Water the soil and let the water sink in
- Place 2 seeds 5 cm / 2 inches apart in the per-moistened soil
- Cover lightly with fresh soil.
Why 2 seeds per hole?
Not all seeds will germinate successfully, and you can always thin out the weaker seedlings later as needed.
Cilantro develops a delicate central taproot. To avoid transplanting seedlings later, always thin out the weaker ones if you have too many plants. The ideal spacing is about 25 cm / 10 inches between plants.
Keep the soil moist but not wet. Use well-drained soil with plenty of organic matter. Avoid complete dry-outs, especially in the hot summer months, as it stresses the plant to bolt and go into premature blooming.
Cilantro is easier to grow during the shoulder seasons and is prone to bolt during the hotter summer months. If your plant starts to develop flowers, remove them to ensure all energy goes into producing more new and tasty leaves.
If you are growing cilantro during the hotter summer months, be prepared to move the pot during the hottest parts of the day.
Grow Cilantro Indoors
If you start your seeds indoors, you will have a longer growing season and a much fuller harvest.
And it is simple and low maintenance.
1. Choose a pot
I prefer using plastic starter pots from recycled materials (7 centimeters or 3 inches) that I have had for years.
Plastic pots help keep the soil moist and prevent dry-outs.
I have used peat pellets and pots made from porous materials, but they are more expensive, and you need to water more, especially on hot days.
2. Choose your soil
You can use regular, well-draining potting soil mix when planting your seeds.
I prefer to use potting and standard gardening soil when I start seeds in pots.
The potting soil has a looser texture and helps me control soil moisture. The richer gardening soil at the bottom of the pot provides nutrients when the roots develop and reach deeper.
Pay attention when you choose your potting soil. Commercial potting mixes are sometimes amended with fertilizer or compost. Seeds do not need extra nutrients to germinate.
3. Fill the pot with soil
Next, fill the pot with 2/3 of gardening soil and then 1/3 of potting soil mix at the top.
Water and let the water run through the soil to moisten it without making it wet.
If the soil compacts, add more potting soil and gently firm using your fingers.
Well-draining soil finds the correct moisture level if you leave the pot alone for excess water to run off.
Pre-moistening the soil is important as it makes it easier to maintain an even soil moisture using a spray bottle going forward.
4. Plant your seeds
I gently crush the seeds before I plant them.
- Place the seeds individually on a kitchen towel or cheesecloth type of fabric.
- Fold it over to cover each individual seed
- Use a rolling pin or glass bottle to apply pressure and crush the seeds gently
- Remove the husk or outer shell of the seeds
Plant the crushed seeds about 1 cm (1/2 inch) deep. Cover the pot.
Lift the cover to improve airflow if you see condensation building on the inside of the cover.
I always plant several seeds and worry about dealing with dense growing seedlings when they are large enough to handle.
Seeds can take up to 3 weeks to germinate. I have compared starting soaked, crushed, and seeds straight out of the seed packet. Gently crushed seeds with the husks removed germinate faster.
In an earlier article, I compared 3 different ways to germinate coriander seeds
5. Cilantro seedling care
Now we wait, and our only job is to ensure that we keep the soil moist but never wet.
Provide at least 6-8 hours of natural sunlight when you see the first leaves sprouting. Double the time if you are using grow lights.
There is no need to fertilize the seedlings at this stage as the roots will find the fertile gardening soil in the lower 2/3 of the pot. Pretty neat, eh?
6. Transplant seedlings to larger posts
If you plant one seed per pot, you can skip this step.
Cilantro has a long taproot and a reputation for being difficult to transplant.
And this is true; the taproot is delicate and does not like to be disturbed.
But I have found that this is only a problem IF you try to separate the seedlings. I have never had any problems when transplanting the whole content of the pot into a larger pot.
As I always plant 3-5 seeds per pot, I need to transplant the seedlings to bigger pots as they develop.
I transplant each pot with 3-5 seedlings into a 20 cm (8 inches) pot.
Now, you should give your plants an extra boost. Give the plants half the recommended dose of a balanced, water-soluble fertilizer.
Give your plants the recommended dosage of a balanced, water-soluble fertilizer every 2-3 weeks from now on.
My rule of thumb is to transplant the seedlings when they are about 5 cm (2 inches) tall.
But if you are worried about hurting the plants, plant the seeds individually and be prepared to thin out the weaker seedlings. Handling seedlings growing tightly together in a group is more complicated and risky.
7. Transplant the mature seedling
When the seedlings have developed to about 10-15 cm (4-6 inches), it is time to transplant them to their final growing place.
When transplanting outdoors, I allow 20-25 cm (8-10 inches) between each pot with seedlings. If the seedlings grow too densely, I thin them out a day or two before the move.
If you are growing rows of cilantro, space the rows about 30 cm (12 inches) apart.
I usually plant 1 – 3 pots with seedlings in a 30 cm / 12-inch pot if they stay indoors. Again, I thin out seedlings as needed.
8. Harvest coriander after 6-8 weeks
You can start harvesting cilantro leaves after about 6-8 weeks.
And why not let one plant bolt and harvest coriander seeds for cooking and starting more plants?
A fully matured coriander plant reaches approximately 70 cm (27 inches).
9. Use fresh cilantro or preserve it for future use
Fresh cilantro is popular worldwide – from Mexico to Southeast Asia.
The cilantro leaves can also be preserved in the freezer for later use. The herb does not dry well and tends to lose a lot of its flavor and aroma.
Harvest Cilantro For The Seeds
There are many ways to use the seeds. But to use for cooking and starting new plants are the most popular.
The good news is that forming seeds is a part of the cilantro plant’s natural life cycle.
But there are ways to speed up the process. The plant will
- form flowers and seeds sooner if we do not harvest leaves
- bolt and go to seed prematurely if exposed to high temperatures
Harvesting seeds is relatively easy. Read all about it in the article: How to harvest coriander seeds
Summary and key takeaways
For some, cilantro tastes like soap, but for most, this herb is a staple and a must to grow at home.
Cilantro is relatively easy to grow and ideal for indoors and growing in the garden.
The key is to crush the seeds gently for improved germination and to know the right time to plant cilantro.
Cilantro grows best in the cooler shoulder seasons of spring and fall. And if you sow the seeds in the height of summer, make sure to avoid full sun.