Compost making is part of the autumn harvest, writes Alice Spenser-Higgs

Autumn arrived in Joburg on Thursday morning last week. There was a chilly edge to the air and a sneaky wind scattered the first of the autumn leaves, prompting me to think about compost.

Autumn is traditionally harvest month and that includes the beginning of a three-month harvest of fallen leaves that can go straight onto the compost heap.

Compost is the cornerstone of organic gardening. Whether you are committed organic gardener or not, it is accepted gardening wisdom that healthy plants need healthy soil and well-made compost is at the top of the list of soil improvers. It supplies a mix of nutrients and coarse organic material that helps aerate the soil.

Digging compost into heavy, clay soil improves drainage because it coarsens the fine soil texture. In sandy soil it has the opposite effect, helping to retain water.

At Garden World’s Autumn Harvest Faire in April there will be talks on organic gardening, incorporating the making and use of compost.

Gardening personality Tanya Visser, who presents a TV gardening programme and edits a garden magazine, will share her organic gardening ups and downs with advice, ideas and inspiration on Saturday April 4.

On Thursday April 23 organic gardener Margie Frayne will talk about how to make organic compost.

Making compost

Talking about organic compost seems like a tautology seeing as compost is organic. But the devil is in the details and making a healthy compost heap means paying attention to what goes onto it and how it is made, so it doesn’t emit methane gas.

The basic method is to alternate wet green material (nitrogen rich) with dried (carbon rich) material, interspersed with activating materials such as manure, already made compost or soil.

The following garden and household waste can be used in a compost heap: dried leaves, grass cuttings, garden waste such as shrub cuttings, spent annuals, weeds (without seeds or flowers), shredded newspaper, vegetable and fruit peelings (except potato peels and citrus), eggshells, tea bags, coffee grounds, ash from a wood fire, manure, pine needles, hay and peanut shells.

Make sure none of the plant material has been subjected to poisonous pesticides and don’t add things such as cat litter or dog droppings containing harmful pathogens.

Other no-no s for the compost heap are meat and fish leftovers, coal ash, magazines, synthetic fibres, glass, tin or plastics.

Use herbs such as comfrey and yarrow which speed up the breaking down process .

The heap can be turned every two to three weeks to aerate it and prevent anaerobic build-up (emits methane gas) or you can put poles or sticks into the compost which provide air channels.

Earthworm compost

Another type of natural fertiliser and soil conditioner is vermicompost which is earthworm manure. It is 10 times more nutritious than commercially bought compost and plants that receive vermicompost are healthier, disease resistant and drought tolerant.

Vermicompost is made by using the earthworm species Eisenia fetida which lives in the top 100-150mm of the soil and feeds on decomposing organic matter. These earthworms have the ability to take in pathogens from the soil and convert them into a life-giving waste (called castings) that contains five times more nitrogen than topsoil as well as high amounts of potassium and phosphate.

The only way to harvest this waste is to keep a wormery. This is simply a container in which the earthworms are kept in conditions that are dark, warm and moist. They are fed whenever necessary on fruit and vegetable scraps, or soft garden waste.

Another by-product is earthworm tea. It is a combination of earthworm urine and the liquid leached from the decomposing material. It can be diluted with water (1:50) and used as a foliar feed, as a rooting agent or as a pre-soak for seeds.

Ready-made wormeries and information about keeping a wormery will also be part of the Autumn Harvest festival programme.

n The Autumn Harvest Faire at Garden World runs from April 4-27. The Manic Organic talk by Tanya Visser is on Saturday April 4 at 2.30pm and cost s R50. The talk by Margie Frayne is on Thursday April 23 at 9.30am and costs R50. Book with Magriet or Annelise on 011 957 2545 or 083 997 6142 or log on to the website www.gardenworld.co.za.

Article from: www.businessday.co.za