18 Common Cilantro/Coriander Plant Problems: How to Fix Them, Solutions, and Treatment

18 Common Cilantro/Coriander Plant Problems: How to Fix Them, Solutions, and Treatment

The Cilantro seed is also known as the Coriander seed. Growing Cilantro in the garden is usually trouble-free. Occasionally, however, a Cilantro gardener may face problems with the plant. Most gardeners grow Cilantro in their herb garden. They find it difficult to grow herbs, but if you avoid common mistakes with growing Cilantro (Coriander), you can make it easier. You can avoid common problems with Cilantro by giving the necessary needs.

Common Cilantro/ Coriander plant problems

Cilantro is drooping

Most herbs grow well until the proper growing conditions are provided. Cilantro is no exception. 

Too much water

Although the Cilantro plants love well-watered soil, too much water can cause problems. If the Cilantro is getting too much water, whether it is due to excessive water or because of excessive rainfall, the plant will wilt. 

Solution – To prevent the Cilantro from wilting/falling due to excessive water logging, let the soil dry before watering. Make sure to plant the Cilantro in the well-drained soil. Also, choose a pot with drainage holes below to grow the Cilantro (Coriander). Add some fungicides when adding potting mix to avoid root rot problems.

Dehydration

If you are underwatering your Cilantro, it is more likely to wilt and fall. The stem loses stiffness, and the rigidity and turgor (pressure in cells) drop to zero if there is a lack of soil moisture. Dehydration also leads to bolting in the Cilantro plants.

Solution – To check that the herb is getting enough water, press your finger a few inches deep into the soil. The Cilantro is underwatered if the soil is dry and your finger cannot enter it. 

Nutrient deficiency

The Cilantro grown in the pot mostly experiences wilting due to a lack of nutrients. Wilting, falling, and eventually, the death of the plant after the leaves turn yellow indicates that the plant lacks nutrients.

Solution – Feed your Cilantro with low nitrogen fertilizer. Such organic seaweed fertilizer is perfect for fertilizing Cilantro plants. Another option is to add dilute fish emulsion to feed plants. You can use compost or cow dung manure monthly. 

Insufficient sunlight

Indoor Cilantro plants wilt, especially during the winter, due to an inadequate supply of light. Sunlight is essential for plant photosynthesis. In case of lack of light, the size of the Cilantro leaves is reduced by the surface area of the leaves.

Solution – To prevent this problem, make sure to have indoor plants on a south-facing window where they can get enough light. If you don’t have enough sunlight for the indoor plants, provide the plants with growing light, like this LED. 

Hard water

Hard water is also one of the possible causes of the fall and wilting of the Cilantro. Heavy water causes salt to be built in the soil. Due to the increased salinity, roots can hardly absorb water from the ground. As a result, herbs begin to wilt.

Solution – To solve this problem, ensure using rainwater or distilled bottled water for plants. If you are using tap water, let it sit 24 hours a day in a bucket, then use it for the Cilantro and other herbs. 

Pests and diseases

Cilantro is prone to bacterial diseases such as soft rot and Coriander blight. Water-soaked lesions are produced on parts of affected plants. These diseases result in the infected plant falling over.

Solution –If you believe that wilting or falling is due to any disease, first of all, recognize the disease with its symptoms. Use natural pest control only for your Cilantro plants. It is because you will use them. Once again, if natural controls do not work for some reason, plant new Cilantro plants. For fungal diseases, if the infection is mild, use baking soda spray or a mixture of Garlic crushed with water on the plants.

Too much direct sunlight

Cilantro is a cold-weather herb that needs 6 hours of direct sun to grow well. Cilantro is more likely to wilt or droop if exposed to too much direct sunlight during the hottest part of the day. 

Solution – Be sure to offer shade to the Cilantro plants in summer; otherwise, the plants will fall, wilt and bolt. Planting Coriander at a place with some shade in the afternoon is highly recommended. Also, add mulch to keep the herbs away and maintain soil moisture.

Bolting

Coriander tends to be straight into a flower, i.e., instead of growing leaves, the plant jumps straight to the flowering stage. Bolting can be caused by heat, transplant, or insufficient water.

Solution – However, there are some things you can do to prolong the stage of leaf production.  Keep the soil moist, and apply the seeds in a place not too shady because they require a sufficient amount of sun to grow properly. Coriander is an excellent plant for sowing from successionally, so sow regularly every 5 to 6 weeks.

Cilantro leaves turning red

The pigment called anthocyanin can cause Cilantro leaves to turn red. When deficient in phosphorus, the plant produces this pigment, an essential factor for healthy plant growth. However, a lack of phosphorus does not mean soil lacks this element. Perhaps it is present in the soil, but the plant’s roots cannot absorb it. 

Solution – Never add phosphorus-rich fertilizer to the ground before confirming the deficiency. High amounts of phosphorus can be harmful to your Cilantro. Another possible reason why the Cilantro leaves turn red is that it is seed-producing.

If you believe it is too early for your Cilantro to start producing seeds (you have not harvested much), it may mean that the temperature is very high. You may also consider getting the varieties of Cilantro seeds that do not bolt very quickly. If you want to discourage bolting, you can trim the plant and remove the seed-producing stems. 

Cilantro leaves turning yellow

Ensure soil drainage if your Cilantro is turning yellow in places. Giving more water can cause limp and yellow leaves in the Cilantro. Another possible reason for yellowing in the Cilantro is the lack of nutrients or burning the plant with too much fertilizer.

Solution – An organic seaweed food or another herb fertilizer will be great for supplementing your plants if this is the case. Make sure that plants do not get scorched by allowing the afternoon shadow. If you use grow lights for your Cilantro, do not grow it too close to the plant. Depending on the increasing light strength, you may need to allow 4 to 8 inches away from the plant.

Cilantro leaves turning white

The Cilantro plant fails to produce enough chlorophyll due to chlorosis; it is a sign that the Cilantro plant is in trouble. Powdery mildew is the second reason for forming a white spot-on Cilantro. Powdery mildew is a fungal disease that occurs when plants are given more water or are more crowded. 

Solution –Several factors are responsible for chlorosis in Cilantro. But basically, it’s due to insufficient light exposure. You can use grow lights for your Cilantro. Mild cases of powdery mildew are restored with the improvement of weather and growing conditions. Potassium bicarbonate spray can be effective for killing powdery mildew spores.

Cilantro leaves turning brown or black

If your Cilantro is turning brown or black, it may be likely due to overwater or root problems. 

Solution – Make sure the soil does not water your Cilantro before drying; the Cilantro needs well-draining soil. Always place a saucer under the pot if growing Cilantro in pots. After watering, remove the excess water from the pot.

Cilantro dying after flowering

Cilantro is an annual herb, so the aim is to grow and flower and then produce seeds for next year. After the Cilantro flowers, the plant dies back, and the leaves taste less than the new growth.

Solution – The key to increasing your Cilantro’s longevity is to prune it out regularly. Once the stems exceed 8 inches, the plant is prevented from producing flowers by pruning them.

Cilantro leggy seedlings 

A lack of light causes leggy seedlings. It may be that the window in which you are growing your seedlings does not provide enough light, or it may be that the lights you are using as they grow are not close enough to the seedlings. Either way, the seedlings will be leggy.

Solution – If you are growing seedlings in the window, try growing them in a south-facing window. If a south-facing window is unavailable, you may consider supplementing the light the seedlings are getting from the window. A small fluorescent bulb is placed within a few inches of the seedling.

Cilantro plant is floppy

If you don’t give enough water, the Cilantro plants are usually drought; too much hot sun is reduced due to soil moisture. The basic two reasons for the Cilantro plant are drought and under-watering the plant (water to control it frequently); other reasons are too hot sunlight and are often not watering to maintain soil moisture levels. It is also possible to use a good soil mix to control the water extracted from the pot quickly.

Solution – Maintain good soil moisture levels to control this. More water if needed on sunny days. If you apply it to a small pot, it is low in the soil, and its moisture content is rapidly loose. Next time try in a large pot with more soil.

Cilantro plants are not growing

The main reasons for not growing Cilantro plants are disease, over-crowding plants, excessive water or underwater water, and high-temperature exposure. These plants will not grow properly under multiple environmental stress. Cilantro plants require light, air, water, and fertile soil for proper growth and nutrition. If these factors are lacking, the Coriander plants will grow inappropriately.

Solution – Plant Coriander in well-drained soil rich in organic matter. Prepare potting mix by adding 50% garden soil, 30% compost, and 20% coco peat. Or buy a potting mix specific to herbs. Remove weeds regularly. Use organic solutions to control pests and diseases.

Cilantro seeds are not germinating 

Seeds failing to break the seed coat

Technically, each Coriander seed has two true seeds locked in a hard, round, brown, or light grey husk. 

Solution – It is recommended that seeds be divided into two parts, broken and soaked in water, before planting for 2 to 3 days. Dividing seeds by pressing. While soaking seeds is unimportant, it helps increase germination rate and speed. If you haven’t prepared the seed before planting, your seeds may fail to break the seed coat and are not growing for that reason.

Seeding very deep in the soil

Another reason is that your Cilantro is not growing because you have sown very deep seeds in the soil. 

Solution – Sow seeds 1/2 to 1/4 inches deep in the ground. If buried too deep, seeds may fail to achieve the required oxygen level critical to growth. Another thing to mention is if you want to grow Cilantro outside the garden, sow the seeds directly there. Cilantro does not need hot temperatures to grow. 

Sowing in high temperature and wrong weather

Seeding causes seeds to suffer from thermal stress due to extremely high soil temperature. 

Solution – Although these are hot weather seeds, they will not rise unless soil temperature is conducive to growth. For successful germination, soil temperature should be between 18 to 24 °C. And the night temperature should be between 10 to 18°C.

Overwater

Coriander seeds need enough moisture to grow. However, maintaining more water and moisture will rot the seed. 

Solution – If the seeds do not sprout even after three weeks, dig and check a few seeds. If the seeds are rotten, sow again and be careful to provide the right amount of moisture. If the soil is too dry, the Cilantro seeds will not grow.

Sowing very old seeds

If the seeds are not properly stored and for the long term (not in a cold and dry place), likely, they are not viable. 

Solution – So, buy fresh Cilantro seeds for planting. You can do a viable test by putting some seeds on a paper towel. If they are viable, they will sprout, so you can plant them in the ground.

Diseases

Soft rot

Small water-soaked lesions near the base of the petioles become soft and brown. 

Solution – Control relies on avoiding conditions conducive to bacterial infections. Plant Cilantro in well-drained soil. Let plants dry before reirrigation. Avoid injuring plants during crops to prevent growth disease. Disinfect all devices regularly. 

Bacterial leaf spot 

Small water-soaked spots between leaf veins turn dark brown to black. The stem can have long dark stripes. Inflorescence turns yellow and brown and scorched. 

Solution – It is difficult to control the bacterial leaf spot and plant pathogen-free seeds. Avoid overhead irrigation, and do not work with plants when they are wet.

Powdery mildew

It appears as small, white, powdery patches on young parts of the stem, leaves, and buds that grow in size and cover the entire area of the leaf surface. The size of the affected leaves decreases and gets distorted. The emergence of the disease is more humid and moderately directed towards temperature (cloudy weather); infection is most severe in shady areas. 

Solution – Protective fungicides applications provide proper protection. You can use the sulfur application in infections that occur early in the season. 

Damping-off

Soft, rotting seeds that fail to grow; the rapid death of the seedlings before emerging from the soil. The seedlings collapse on the soil line after coming out of the soil due to water-soaked reddish lesions. 

Solution – Avoid planting in poor drainage, cold, wet soil; planting in raised beds will help in soil extraction. Plant high-quality seed that grows fast; treat seeds with fungicides before planting to eliminate fungi pathogens.

Pests

Slugs and snails

Slugs and snails will feed young Cilantro plants. They can be identified by the damage they cause. 

Solution – Check the plants at night and remove the slugs and snails from the hand. Covering the soil around the plant with crushed eggshells or grit can have some effect. If other methods are inadequate, scatter eco-friendly slug pellets.

Aphids 

Aphids are juice-sucking insects that can affect young plants faster, stopping growth.

Solution 

Clean the small colonies of aphids on Coriander with a moist cloth. Encourage natural predators like ladybirds and whiteflies. Pesticide sprays are available for aphids.