Growing Silverbeet

Latest Update 19th March 2017.

Silverbeet (Swiss Chard)
  • Two sowings a year of 2 plants are enough for 2 people.  Harvesting is almost continuous, just a few leaves each week.
  • Its nice steamed with sea salt, ground pepper, mixed herbs and a little nutmeg.  I use the stalks in vegetable soups.
  • Grown organically silverbeet is very nutritious containing lots of vitamins and minerals and an excellent source of dietary fibre.
  • It can be grown all year, but needs extra protection from the sun in summer.
Details.
  • Variety:                                                    Rhubarb Silverbeet & Fordhook Silverbeet.
  • Family group:                                           Chenopodiaceae.
  • Crop rotation group:                                  Heavy Feeders.
  • Garden bed type:                                      Garden Ecobed.
  • Recommended soil pH:                             6.0 - 7.5.
  • Minimum sun per day:                              4 hours.
  • Plant spacings:                                        500mm.
  • Weeks to harvest:                                     7 - 12 weeks.
  • Good companions.                                    Beetroot. Lavender. Onions.
  • Climate:                                                   Warm temperate
  • Geography:                                              Southern hemisphere.
Nutrition.
  • This food is very low in cholesterol. 
  • It is a good source of thiamin, folate, phosphorus and zinc, and a very good source of dietary fiber, vitamin A, vitamin C, vitamin E (alpha tocopherol), vitamin K, riboflavin, vitamin B6, calcium, iron, magnesium, potassium, copper and manganese. 
  • More from nutrition data.self.com.
Growing Conditions: 
  • They grow best in full sun.
  • Silverbeet can be grown all year round, but they are best grown in cooler conditions.  
  • Keep shaded when grown in summer with 21% shadecloth/exclusion netting. 
  • Extra shading should be used in very hot weather (over 40 deg C) using 75% shadecloth.
  • They need well structured rich organic soil.
  • The soil must be kept moist at all times.
Soil Preparation.
  • Clear a space for Silverbeet in February and add a 60mm layer of home made compost.  Cover with 50mm of fresh straw mulch.
  • Leave the bed for 4 weeks to build up worm and microbial activity.  Move the mulch to one side before sowing the Silverbeet.
Growing Instructions.
  • In March, soak four Silverbeet seeds in captured rainwater for 24 hours.
  • Sow them in Jiffy pots (2 per pot) filled with good quality organic propagating mix .  Sow them about 10mm deep.
  • Bury the jiffy pots in the compost layer of a propagator up to their rims.
  • Because each Silverbeet seed capsule contains up to 4 individual seeds, pinch off the stems of all but one of them at ground level.  Keep the strongest seedling only in each pot.
  • When the seedlings are about 100mm tall and without removing them from their Jiffy pots, plant the seedlings in the prepared bed.
  • Water them well with rainwater containing seaweed extract (suppliers dilution rate).
  • Cover the soil with fresh mulch as soon as the silverbeet is established.  
  • Apply a foliar spray of aerated compost tea every 4 weeks when all the other edible plants are sprayed.
Repeat sowings.
  • Prepare the soil in August, and sow another pair of Silverbeet in September.
  • Silverbeet should not be grown more than once in the same spot in the same season.  Follow other members of the crop rotation group instead.
Harvesting and Storage
  • Silverbeet can be harvested continuously a few leaves at a time.
  • You can store Silverbeet in your freezer.  Simply wash dry and roughly chop the leaves, and pack them in large plastic zip bags.
Organic Pest Control. 
  • Slugs and snails.
    • Silverbeet should be protected against slugs and snails using self adhesive copper tape bonded around the base of your Ecobeds.
    • If these molluscs get into your Ecobed as eggs laid in your compost, kill them with organically approved iron based snail pellets as soon as you discover them.  You should only need to use a small number of pellets.
  • Greenhouse whitefly.
    • Aerated compost tea increases silverbeet's resistance to whitefly damage.
    • Exclusion netting is very effective against whitefly, but they are very small and will occasionally breach your defences, so you will need to check your crop regularly. 
    • Control any infestations by spraying your crop thoroughly with organic horticultural oil (Eco-oil in Australia) as early in the whiteflies life cycle as possible.
    • Spray again in a few days to ensure second generation whitefly do not survive. 
  • Root knot nematodes.
    • A 4 year crop rotation plan is the best cure for root knot nematode.  They do not prosper when their host plant is removed to another bed, and after 4 years, their effectiveness as a plant pathogen is substantially reduced.
  • General:
    • Regular applications of aerated compost tea boost the natural defences of Silverbeet 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.
    • Exclusion netting stops birds digging up worms in your Ecobed, and takes the edge off hot sunshine with a 20% shade factor.