Growing Coriander

Latest Update 4th October 2016.

Coriander (Cilantro)
  • I grow Coriander as a culinary herb and as an attractant for predatory and pollinating insects, close to my veggie patch where it does most good.
  • Coriander provides many health benefits and all parts of the plant are edible.  
  • Coriander has a distinctive zesty, aromatic flavour, similar to a blend of lemon and sage.  It can be used fresh or dried and crushed into a course powder for sprinkling on your meals.
  • Coriander leaves are best added at the end of cooking or as a garnish on dish as heat can reduce its potency.
  • It is largely pest free, and is at home in Melbourne's hot dry summers (although it bolts to seed in hot weather).
Details.
  • Variety:                                                           Coriandrum sativum. 
  • Family:                                                           Apiaceae.
  • Garden bed type:                                             Drip line irrigated bed.
  • Recommended soil pH:                                    6.5 -7.5.
  • Minimum Sun per Day:                                    3 hours.
  • Plant Spacings (centres):                                 300mm.
  • Companions:                                                  Cabbage, Carrot, Chervil, Dill.
  • Climate:                                                         Warm Temperate.
  • Geographic Hemisphere:                                  Southern. 
Nutrition.
  • This food is very low in Saturated Fat and Cholesterol. 
  • It is also a good source of Thiamin and Zinc, and a very good source of Dietary Fiber, Vitamin A, Vitamin C, Vitamin E (Alpha Tocopherol), Vitamin K, Riboflavin, Niacin, Vitamin B6, Folate, Pantothenic Acid, Calcium, Iron, Magnesium, Phosphorus, Potassium, Copper and Manganese.
  • More from nutrition data.self.com.
Growing Conditions:
  • Coriander prefers sandy soil but grows well in most organically active soils. 
  • They grow well in hot dry conditions and resist drought. 
  • Coriander needs well drained soil and full sun.  
  • They have a deep tap root which mines the subsoil for micronutrients. 
Soil Preparation.
  • In Spring, clear a space for the Coriander by removing old mulch, dead leaves and unwanted organic material.  Choose a place where Coriander has not been grown for several years.
  • Apply a 60mm thick top dressing of homemade compost and cover with straw mulch. 
  • Leave for a month before planting to increase biological activity in the soil. 
Growing Instructions.
  • Coriander is a perennial plant grown from seed as an annual. 
  • Sow coriander seeds in August on the surface of an organic seed growing mix in a mini pot, and cover lightly with mix.
  • Soak the mini pot for an hour in a tray containing 10mm of water (preferably rainwater).  The water will wick up into the soil without flooding it. 
  • Sink the mini pot up to its rim in a propagator's wicking media.  This will keep the soil moist until the seedlings are ready to transplant.  Protect the seedlings against frost if necessary. 
  • After 4 weeks transplant the seedlings individually into organic potting mix in jiffy pots and return them to the propagator.
  • After a further 4 weeks clear a small space in the mulch in the prepared bed(s) and plant the seedlings.
  • Return the displaced mulch as soon as the coriander is established.
  • Note** The above procedures are only required when growing coriander for the first time as it will readily self seed and produce lots of seedlings if allowed to flower.
  • Apply a foliar spray of aerated compost tea every 4 weeks when the other edible plants are sprayed.
  • Coriander is a light feeder but will benefit from a top dressing of home made compost in winter.
Harvesting and Storage
  • Coriander can be harvested at any time, but don't strip the leaves too much or you could set the plants growth back some time as it recovers.
  • Begin using the leaves as soon as the plant is large enough to spare some.
  • You can dry coriander leaves in a dehydrator.  Once the leaves are dry, crush them and store them in an airtight container.
Organic Pest Control. 
    • I grow my herbs in a drip irrigated raised bed, and run copper tape around it 100mm off the ground.
    • Copper tape is a very effective barrier as the slugs and snails get a small electric shock when they come into contact with it, and they retreat to less hostile surroundings.
    • Occasionally I get one or two juvenile snails in my raised beds.  I believe they get into the bed as eggs though the compost heap.  When this happens, I use a few iron chelate snail baits to round them up.  These bates are approved for use in organic gardens, but I only use the bare minimum to do the job.
  • Greenhouse whitefly.
    • Aerated compost tea strengthens the plants foliage against whitefly damage.  
    • Control any infestations by spray your crop thoroughly with organic horticultural oil (Eco-oil in Australia).
    • Spray again in a few days to ensure second generation whitefly do not survive.
  • Aphids (greenfly).
    • Use the same method as described above for whitefly.
  • General:
    • Regular applications of aerated compost tea boost the natural defences of plants by colonising the leaf surfaces with beneficial microbes.  They defend the plant against airborne pests and diseases.
    • Similarly, proper soil preparation including regular applications of home made compost boosts the community of beneficial microbes, which defend the plants roots against plant pathogens.