When you’re growing organic cilantro for it’s leaves, it’s called cilantro. It is also grown for its dried seeds; the seeds are called coriander.
Growing cilantro as an herb dates back to 3000 B.C.; cilantro shows up in Sanskrit writings in 1500 B.C.
Coriander seeds were discovered in several tombs of Egyptian Pharaohs as well as in Grecian ruins dating back to the Bronze Age.
Growing cilantro in America started around 1670 and was one of the first herbs/spices grown by the early colonists.
WHEN TO PLANT
In Northern climates, you can plant cilantro a few weeks before the last frost. If you plant cilantro every couple of weeks you can harvest it throughout the summer.
In Southern climates, you can plant in the fall for spring harvest.
It takes about 30 to 40 days from planting to harvesting cilantro for it’s leaves; you can harvest a 2nd picking in 10 to 14 days after that.
For coriander seeds, it’s about 40 to 50 days until harvest.
WHERE TO PLANT
Cilantro/Coriander requires a minimum of 6 hours of direct sunlight – preferably 8 or more – for optimum growth.
Cilantro/Coriander develop better flavor with more sunlight. Strong light creates more fragrant oils in the foliage and stems.
When it gets hot in the summer, cilantro will often “bolt.” Bolting means it goes to seed. You can plant “slow bolting” varieties in the shade of taller plants in hot climates to keep it from bolting, unless you are growing it specifically for coriander.
When you choose where to plant cilantro/coriander, focus on soil that drains well. If you dig a 12″ x 12″ x 12″ hole, fill it with water, and allow it to drain, it should drain within 3 hours or you should add organic matter and possibly sand to your soil to aid the drainage.
Like other herbs, such as sage, it is thought to be beneficial not to add too many nutrients to your soil or it could adversely affect the flavor
PREPARING THE SOIL
Cilantro/Coriander grows well in a pH level range of 6.0 to 8.0, although it performs best in the middle of this range.
For best results with organic cilantro, rototill or spade in 2 or 3 inches of composted organic matter or manure into the top 6 inches of your garden soil.
CHOOSING THE BEST SEED VARIETIES FOR YOUR AREA
When growing cilantro for the leaves, you’ll want to grow slow bolting varieties. Consult with a reputable seed supplier when choosing your variety.
Slow bolting varieties are also better in hotter climates as they won’t go to seed as quickly.
If you’re harvesting the coriander seeds, most varieties work fine as all will go to seed at some point.
As always, consult your local county extension to find out if there are any diseases that are common to cilantro/coriander in your area and get advice on resistant varieties if applicable.
SEEDS AND GERMINATION
Because Cilantro grows a long taproot, it’s preferable to plant directly in your garden. It can be started indoors though.
Cilantro will germinate in soil temps ranging from 45° to 85°F; optimal germinating temps are 60° to 75°F. The seeds will germinate in 2 to 3 weeks typically.
Because cilantro is frost resistant, it can be planted quite early in the spring, even in Northern climate zones.
Most varieties of cilantro/coriander grow to about 12 to 15 inches in height.
Many gardeners grow cilantro for both herb and seeds, which, as we’ve already mentioned a few times, are known as coriander.
If you’ve let your cilantro bolt, cut the flower heads off, leaving about 8 inches of stem, then bundle bunches of stems, tying them together with a string or rubber band.
Put the flowers and stems upside down in a brown paper bag and tie it closed around the stem, then hang it in a dark and dry location.
In a week or so, shake the bag/stems to loosen the seeds, then remove the seeds. Store them in a glass jar in a cool, dry location until you want to use them for flavoring or planting.
GETTING STARTED INDOORS
If you do want to plant your seeds indoors in the late winter or early spring, you can do so using a grow light stand or other fluorescent lighting.
Turn your lights on for 14 to 16 hours a day, 4 to 6 inches above the soil or seedlings.
Soil blocks or peat pots are ideal for starting cilantro as they can be transplanted into your garden without disturbing the plant’s roots.
Use a good quality sterile potting mix to start your seeds in; adding alfalfa meal or compost will help the plant’s early growth.
Plant your seeds about ¼ inch deep, 2 seeds per pot. Once the plants are a couple inches tall, thin the weaker plant by cutting it off with a scissor at ground level.
TRANSPLANTING CILANTRO/CORIANDER OUTDOORS
When cilantro seedlings are 2 to 3 inches tall, they’re ready to transplant to your garden or flower bed.
To prepare cilantro for transplanting to your garden, you need to “harden off” your plants.
The process of hardening off seedlings entails moving your plants outside daily; a few hours at first, then increasing the time daily for 7 to 10 days until the plants become accustomed to strong sunlight and cool nights.
Cilantro has a sensitive taproot, so the best way to transplant them is in soil blocks or peat pots. Cut the bottom out of the peat pot or just place the soil blocks in a holes large enough to accept them.
Tamp the soil in around the transplants enough to keep them from moving around but not so much as to make it difficult for the roots to expand.
Plant cilantro in double rows 12 to 18 inches apart, leaving them plenty of room to dry out after watering or a rainstorm.
PLANTING CILANTRO SEEDS IN YOUR GARDEN
As mentioned above, cilantro is a cold-hardy plant and can be planted up to 4 weeks before the last expected frost.
Mark your double rows (or plant as a companion to tomatoes or other plants) at 12 to 18 inches apart, with 30 to 36 inches spacing to any other rows or other garden plants.
Plant your coriander/cilantro seeds ¼ to ½ inch deep and 2 inches apart. Lightly press the soil down on the seeds and water.
If you want to plant successive plantings, repeat this process every 10 to 14 days into the late spring and again toward the end of summer if desired.
BEST PRACTICES FOR GROWING GREAT CILANTRO/CORIANDER
If you’ve planted seeds and you have more than one every 12 to 18 inches, thin them out to that distance once they’ve reached 2 to 3 inches.
Unless you’re growing cilantro for coriander seeds, you’ll want to grow your cilantro in the cooler parts of the growing season to keep it from bolting (going to seed).
To prevent bolting, you can use a mulch like barley straw (our favorite) to keep the soil cool. Mulch also keeps moisture in the soil. If the soil temperature reaches 75°F, cilantro will bolt.
Overhead watering may reduce your cilantro’s seed yield.
It is unusual to need to add compost or composted manure during the growing season unless your plants show deficiencies such as yellowish-green leaves. As with most herbs, too many nutrients will negatively effect the flavor of your cilantro.
The one fertilizer we are recommending for every plant in your garden, including cilantro, is a brand new product we tested last year called Organic Garden Miracle™. This past gardening season we tested this liquid organic leaf spray fertilizer in our gardens. We sprayed fruits, veggies, and herbs every couple weeks and they were more robust than the unsprayed plants, and the flavor was better as well – aromatic, sweeter, and juicier. We’re impressed.
MULCHING & WEEDING
We love mulch, particularly seed-free mulches like barley straw or chopped leaves.
Adding 2 to 5 inches of mulch will keep weeds down, moisture in, and generally create happier cilantro plants.
If you don’t have access to mulching materials and need to weed, carefully hand-pull or cut off the weeds at the soil level near your plants and hoe between the plants and rows if rototilling isn’t an option.
CILANTRO WATERING REQUIREMENTS
Growing cilantro needs good moisture about 8 inches into the soil. The best watering practice is a good soaking about 1 time per week.
If your soil is sandy, you may need to water more frequently, but using a good mulch layer around your plants will keep them moist. Check the soil moisture every few days until you get a feel for how the air, soil, water, and mulch interact.
It is best, as with most garden plants, not to water using overhead sprinklers. However, with cilantro, the reason is less due to fungus than because it affects the flavor of the coriander seeds.
Commercial growers almost always use drip irrigation.
Don’t allow your plants to wilt, but don’t make your soil soggy either. You can tell if your soil’s too wet if you can compact the soil easily in your hand.
Wet soil can induce root rot of varying types.
COMPANION PLANTING AND ROTATION CONSIDERATIONS
Cilantro is said to repel harmful insects such as aphids, spider mites and the potato beetle.
Planting cilantro near potatoes, therefore, is a good practice.
Any plants that are susceptible to aphids will benefit from cilantro planted in the vicinity. Carrots, cabbage, asparagus, spinach, etc. all benefit from cilantro.
Growing cilantro is benefited by legumes planted near it. Legumes such as peas and beans take nitrogen from the air and deposit it into the soil. This is beneficial to most garden plants.
Don’t plant cilantro near to fennel, though. It is an allelopath to most garden plants, which simply means it can inhibit your other garden plant’s growth.
WHEN TO HARVEST CILANTRO/CORIANDER
Once cilantro reaches 6 inches in height, you can selectively harvest a few leaves from the plants outer stems. It’s best to leave the center stalk alone.
If you’re going to collect the coriander seeds, wait for the seed stocks to form, then follow the instructions in the section above called “Saving Seeds.”
Even after the flower and seed stalk forms, you can still harvest leaves.
While it’s best to pick cilantro when you’re ready to use it in a salad or another dish, sometimes you need to have it last just a little longer.
The best way we know of is to put it into cold water in a glass (kind of like flowers in a vase) and put it in your fridge.
You can also bundle it without washing it and it will keep for a couple days or so.
Drying cilantro, we’ve discovered, doesn’t seem to be a good way to store it as it loses most of its flavor in the drying process.
You can freeze cilantro also…it’s not as good as fresh cilantro, but much better than dried. Just put it dry into a zip-lock style plastic bag and stick it in your freezer for later use.
We discussed storing coriander seeds in the “Saving Seeds” section above, so I won’t cover that again here.
PREVENTATIVE AND NATURAL SOLUTIONS TO COMMON PESTS
Leafhoppers are always a threat wherever cilantro is grown. Leafhoppers may transmit a disease called Aster’s Yellows.
Leaf hoppers are small, somewhat triangular variable-colored insects that hang out on the undersides of leaves or on stems.
They suck the juices out of plant leaves and inject stunting microorganisms into the plant’s leaves. They may stunt your cilantro’s growth or if the infestation is heavy, even kill your plants.
Insecticidal soap spray, neem oil, pyrethrum, and/or Diatomaceous Earth (DE) have all been effectively used by organic gardeners to control these pests.
Aphids are a common pests that can be found on the undersides of your cilantro leaves. You’ll know they’re there if you see leaves turning yellow and crinkling or curling.
Aphids suck the juice from your plant leaves and leave a sticky substance behind. The only beneficiary of this process is ants, who harvest the sticky sweet stuff.
The best solution to aphids is to import ladybugs to your garden. They feed on aphids and are very effective in ridding your plants of these little green, gray, or brown bugs.
Another solution is to “wash” them off with a hose and high-pressure spray nozzle or an organic insecticidal soap. DE has also been used successfully.
Here’s a recipe for a homemade insecticidal soap that you can try: 1 cup mineral oil, 2 cups water, and 2 tablespoons organic dish soap. Mix and put into a spray bottle or pump up sprayer.
Another pest, the armyworm, have larvae that come in various colors from black to dark greenish-brown; they have dark brown, white, and orange stripes the entire length of their abdomens.
The mature larvae is about 1.5 inches long and its head is yellow-brown with brown streaks that gives the worm a mottled appearance.
The armyworm pupae are easy to spot when you’re cultivating your garden…they live in a brownish-colored shell just below the surface of the soil. I squish them when I see them or feed them to the chickens.
The moth of the armyworm is about 1 inch long and has a 1.5 inch wingspan, is light brown to tan-colored with a white spot on each forewing.
The moth lays eggs in rows on the undersides of the leaves of the host plant; after laying the eggs, the moth rolls the leaves around the eggs for protection.
Armyworms feed mainly on the leaves of the plants, leaving droppings under the plants and severed leaf materials on the ground.
For gardeners, the easiest way to control armyworms is to handpick them and drop them in a bucket of warm soapy water to drown them, or feed them to the chickens if they’ll eat them.
Aster’s Yellow Disease is transmitted by leafhoppers (see above section). This disease makes the plant grow spindly and the flowers turn yellow and makes the plant become sterile.
Controlling leafhoppers is the best way to control aster’s yellow disease. If the disease shows up, destroy the diseased plants.
As mentioned in the above section, insecticidal soap spray, neem oil, pyrethrum, and/or Diatomaceous Earth (DE) have all been effectively used by organic gardeners to control these pests.
Damping off (seedling rot) may affect cilantro seedlings as they germinate. This group of fungi is spread in cool, damp soil, so make sure you plant in well-drained soil.
Soaking your seeds in a compost tea or mixing hot compost (direct from your compost pile) with the seeds is said to inoculate the seeds and seedlings against this disease.
You can also purchase resistant seed varieties to damping off.
If you’re starting plants indoors, use sterile potting soil, and don’t overwater your seeds or seedlings, and don’t plant the seeds too deep.
Leaf spots are caused by bacteria is caused when infected water is splashed on the cilantro’s leaves. Overhead irrigation is often at fault for spreading this bacteria.
Leaf spots appear as tan spots with purple borders.
Using drip irrigation to ensure dry leaves is the best prevention as you can’t get rid of leaf spot once it’s infected your plants, although neem oil and organic copper-based fungicides can control the spreading of leaf spots.
Root Knot Nematodes are plant parasites that are shaped like worms. They are microscopic and invisible to the human eye.
Plants that aren’t getting enough water are the most susceptible to this parasite.
Root knot nematodes affect plants by causing them to wilt, be stunted, reducing crop yields, and sometimes even killing plants.
Underground, root knot nematodes create knotted roots or stunted roots. The knot sizes will vary depending on the species of nematode invading the plant’s roots.
The best cure for root-knot nematodes is prevention. Purchasing resistant plants or varieties is your best defense against this disease.
If you have nematodes in your garden, make sure you isolate the area and leave it fallow for 2 to 3 years.
Also, don’t allow water to run-off from these areas into unaffected areas or the disease will spread.
For a short term solution to root-knot nematodes on the upper surface of the soil, you can use a process called “solarization.” Moisten your soil, then cover it with clear plastic through the hottest part of the summer.
If you can get your soil temps up to 130°F for as little as 5 minutes, you’ll kill the nematodes and eggs as deep as you can get that temperature.
There is an organic fungicide called azadirachtin that is listed by OMRI as organic. I haven’t researched it though, so if anyone knows something about it, be sure to post your findings below.