Do you love growing herbs? If so, cilantro (coriander) must be on your list as it is easy to grow and maintain. Besides that, from the Middle East to Asia, many dishes are incomplete without the nice aroma and appealing touch of cilantro. Of course, homegrown herbs taste much better than store-bought ones. In this post, you will find out about germinating cilantro seeds, how long it takes to germinate coriander seeds, how to germinate cilantro seeds on paper towels, reasons why cilantro (coriander) is not germinating, and what to do to successfully germinate cilantro seeds.
Cilantro is an edible plant and used in two ways- the fresh leaves as a herb and its dried seeds are used as a spice in cooking. Its seeds are named “coriander”. Most gardeners face challenges while germinating these seeds. If you are facing the same problem, you are in the right place.
The cilantro will not be germinating if the seeds are overwatered or underwatered. Coriander seeds also won’t be germinating if seeds are too old and have not been stored properly, or in very high or low temperatures.
How long do cilantro seeds take to germinate?
Before we discuss the reasons why cilantro seeds aren’t germinating, it is important to learn how long cilantro seeds actually take to germinate. Normally, under favorable conditions, cilantro seeds take about 7 to 21 days to germinate.
Generally, coriander sprouts are too delicate. If you’re transplanting coriander plants, they may not do well. There are chances of damaging the taproot while transplanting them. Therefore, it is recommended to sow these seeds directly in the pots in which you want to keep them later. You can also start seeds indoors as it will give you a head start in the growing season.
When to sow cilantro seeds?
Normally, coriander seeds are sown in late spring or early summer for cooler zones, mainly 2 to 3 weeks after the last frost. If you wish to get multiple harvests, you can keep planting more cilantro up to the mid of summer. For warmer zones, these seeds can be sown again in the fall. Once they germinate, make sure to space them around 10 inches (25 cm) apart.
However, if you want to have a supply of fresh cilantro in winter, you can sow some seeds in the beginning of autumn and even in winter. Because cilantro is very sensitive to heat and day-light photoperiod, sowing cilantro seeds in spring or winter can definitely result in a good harvest. If temperatures indoors are low in winter, you can cover the seeds with a thin film or use an under heater to keep warm temperatures.
Reasons for cilantro not germinating
Planting cilantro is not as difficult as you may think. But some gardeners make a few mistakes that prevent cilantro seeds from sprouting. Let’s learn what the reasons and solutions are for cilantro germination.
Reason 1: Seeds failing to break the seed coat
Technically, each coriander seed contain two true seeds which are enclosed in a hard, round, brown, or light grey husk. It is recommended to prepare the seeds by splitting them into two halves, breaking the coat and soaking them in water before planting for 2-3 days. Splitting seeds by applying pressure is called scarification.
Though scarification or soaking the seeds is not crucial, but it helps increase germination rate and speed. If you haven’t prepared the seed before planting, maybe your seeds fail to break the seed coat and are not germinating due to this reason.
Reason 2: Planting seeds too deep into the soil
Another reason your cilantro (coriander) is not germinating is because you have sown seeds too deep in the soil. Sow the seeds ½ to ¼ inches deep in the ground. The seeds need oxygen for germination. If buried too deep, the seeds may fail to get the required oxygen levels crucial for growth.
Another point to mention is that if you want to grow cilantro outdoors in the garden, sow the seeds there straight away. Cilantro doesn’t need warm temperatures to germinate. In fact, cilantro doesn’t do well with transitions from indoors to outdoors and other way round. If you are going to grow them indoors, sow the seeds indoors and keep the plants indoors as well.
Reason 3: High temperatures and sowing in wrong season
Planting seeds when the soil temperature is extremely high causes the seeds to suffer thermal stress. Though these are warm-season seeds, they’ll not grow until the soil temperature is favorable for the growth. For successful germination, the temperature of the soil should be between 64-75 degrees Fahrenheit (18 to 24 degrees Celsius). And the night temperature should be between 50-64 degrees Fahrenheit (10 to 18 degrees Celsius).
What is more, cilantro plants don’t generally like high heat, and will start bolting. Make sure your cilantro can receive some afternoon shade as well. The same goes for seeds – they dislike high temperatures, so will have issues germinating. This is why it’s better to sow seeds in mid or late spring, instead of summer. Even though cilantro doesn’t like high heat, it mostly needs full sun with some shade to prevent rapid bolting. It also likes lots of water.
Reason 4: Overwatering
Coriander seeds require enough moisture for germination. However, overwatering and moisture retention will cause seed rot. Make sure to keep the soil moist but not waterlogged. If the seeds are not sprouted even after 3 weeks, check a few seeds by digging. If seeds are rotten, sow again and be careful to provide the right amount of moisture. On the other hand, cilantro seeds will not germinate if the soil is too dry.
Reason 5: Sowing seeds that are too old
If the seeds are not stored properly and for a long period of time (not in a cool and dry place), there’s a chance that they are not viable. Sowing such seeds can be a headache as they will not germinate. Therefore, purchase fresh cilantro seeds for planting. You can perform a viability test by germinating some seeds on a paper towel. If seeds are viable, they will sprout, which means you can plant them in the ground.
Reason 6: Mice and birds are eating freshly sown seeds
Keep an eye on the pests such as the mice in your garden/area. Mice and birds love to eat freshly sown/grown seeds. If you notice mice droppings near the seed bed, there’s a possibility that mice have eaten the seeds. So, install mice traps in your garden.
If you have a lot of pests in your area, germinating the seeds indoors in the seed trays is a good idea. Finally, plant them outdoors after the seedlings have developed. Birds can also get your newly planted outdoor seeds. For keeping the birds away, cover the seed planter with row cover, mesh, or cloches. You can even use kitchen splatter guards for this purpose. Some seedling starter trays, like these ones, come with dome covers.
How to germinate cilantro on paper towels?
You might be wondering if germinating cilantro seeds on a paper towel is possible. Yes, you can germinate coriander on newspapers, paper towels, and filter papers as they provide an ideal germination medium. Not only are they pathogen-free, but you can also control the moisture content during the germination process. Besides, you can easily observe if the seeds have germinated or not.
The only disadvantage to germinating cilantro seeds on paper towels is that the delicate sprouts need to be transplanted to other moist mediums. The sprouts will not grow if the taproot gets damaged during transplanting. Therefore, you should carefully place the new plants in another growth medium \9such as vermiculite or moist soil).
Let’s find out how you can germinate cilantro on paper towels.
Materials required:
- 1 zip lock bag
- A piece of paper towel
- Some coriander seeds
Procedure:
- Take a piece of paper towel and cut it into two halves.
- Moisten one-half of the paper towel.
- Place 5 to 6 coriander seeds on one-half paper towel.
- Take the other piece and place it over the seeds (cover them)
- Now place it in a zip lock bag and seal the bag.
- Leave at room temperature for 1 week, away from the direct sunlight.
- This bag will act as a mini greenhouse. It will retain the heat and moisture content for seed germination.
- The seeds will sprout within 1 week.
- Use vermiculite or moist soil for transplanting the sprouts.
- Avoid pushing the cotyledons (embryonic leaves) deep into the soil. Instead, use tweezers and gently place the tiny plants into holes in the soil.
- Once the seedlings develop 3 to 4 true leaves, you can transplant them outdoors onto the ground, or indoors in the pots.
Soaking coriander seeds before sowing
Most gardeners suggest soaking coriander seeds before sowing. For this, soak the seeds in water for 24 hours and rinse with fresh water. You can plant these soaked seeds both indoors and outdoors.
For indoors, spread the soaked seeds over the potting mix, containing compost or vermiculite. Select a warm spot in the room for placing the seed tray. Also, you can choose to get a seedling heat mat with a thermostat to control temperatures, like this one. This will be great for germinating seeds if you don’t have any warm spots in your room.
Cover the pot with cilantro seeds, to cut off the light supply. That’s because at this point, photosynthesis is not taking place as there are no leaves. Before covering, mist the soil. Make sure to keep checking the soil regularly. Mist the soil if it is dry. Once the tiny sprouts emerge, there is no need to cover the pot. Transfer the seedlings to a sunny location where they can receive 6 to 8 hours of direct sunlight. The seedlings will emerge within a minimum of 3 to 4 days and a maximum of 1 week.
For outdoors, simply spread unsoaked seeds on the ground, in rows – 3 to 4 inches apart. Slightly cover the seeds with mulch. Make sure to keep the seeds moist. If the weather conditions are suitable, the cilantro will germinate within 2 weeks.
So, the conclusion is, soaking seeds can help increase the germination rate. Overall, there is no difference between plants grown from soaked or unsoaked seeds. Only the soaked seeds tend to germinate faster and earlier as compared to unsoaked seeds.
Can you plant store bought coriander seeds?
Most beginners ask if they can germinate the coriander seeds bought from grocery stores. The answer is yes, you can grow coriander seeds bought from the store. However, sometimes these seeds are old and are not stored properly. For this reason, the germination rate of these seeds can be low. It might happen that only a few seeds will germinate from the batch.
Therefore, if you are planning to plant cilantro, it is recommended to purchase good-quality non-GMO seeds with high germination rates, like the ones. Make sure to buy seeds from authentic dealers.
Thank you for reading this post on cilantro, or coriander seeds not germinating. To learn more about growing herbs, see this page.