What is an organic garden?
An organic garden is one that is grown without the use of chemical pesticides, herbicides or fertilizer. Stricter organic standards such as those promoted by the UK’s Soil Association also exclude the use of genetically-modified plants.
For example, excess nitrogen and phosphate from fertilizer is washed into rivers and ends up in the sea, where it reduces the amount of dissolved oxygen in the water and suffocates life. The use of chemical fertilizers in the USA’s Mississippi River Valley has caused an 18 000 km2 dead zone in the Gulf of Mexico, where no marine life now exists.
Organic methods instead maintain soil fertility primarily through the use of compost, with no negative impact on wildlife or the environment.
Chemical pesticides and herbicides are hazardous to human health when residues are ingested after application, or after eating conventionally-grown fruit and vegetables. These poisons can bio-accumulate in the body over time, and result in birth defects, tumours, blood and nerve disorders, and endocrine disruption, amongst other conditions. Organic growing methods avoid these impacts by using biological means to control pests, such as encouraging beneficial wildlife and companion planting.
While the impact on human health is not yet certain, the danger of genetically modified plants is that they can cross-pollinate with other varieties and effectively wipe out species, reducing biodiversity. Organic methods make use of non-GM seeds or open-pollinated seeds which have adapted to a region and which have naturally built up a resistance to pests, diseases and weather conditions.
5 ways to garden organically
#1: Make your own compost
Why throw away all your fruit and vegetable leftovers and garden cuttings, and then go and buy compost? It’s easy to make your own, and you’ll save money.
Buy a plastic compost container (e.g. in a drum form that can be turned easily), or make one from leftover pieces of wood, wire netting or old tyres. Fill the container with a mix of different plant materials, with equal portions of dry clippings and fresh vegetable waste. Turn and re-mix the heap at least twice until it is full, then leave it for six months to mature before mixing the compost into the soil. Ideally, create two smaller heaps; you can leave the first one to mature while you fill up the second one.
#2: Use open-pollinated seeds
Avoid genetically modified seeds and instead choose from an astonishing array of heirloom, organic and open-pollinated seeds. This will help to preserve local genetic diversity, and also provide you with real variety for a nutritious diet if you grow fruit and vegetables.
You can buy these seeds online at http://www.organicseeds.co.za or http://www.livingseeds.co.za. Save seeds and plant them again next season for free – something you’re not legally allowed to do with GM seeds.
#3: Rotate vegetable crops
If you have a vegetable garden, understand that planting and re-planting the same crop in the same place depletes the soil of nutrients and leaves the plants more vulnerable to disease. Instead, plant a different crop each season, until at least 3 years have passed.
Find out which type of plant family you’re planting, and what type you should plant there afterwards to replenish the soil. For example, after you’ve harvested potatoes, tomatoes or peppers, you should plant legumes such as peas or beans to return the right level of nitrogen to the soil.
#4: Use companion planting
Combining and mixing crops helps to reduce attacks from pests and disease, as they attract and support insect predators and pollinators. Growing herbs with strong scents such as rosemary or lavender, or bright yellow or orange marigolds, help to “hide” your fruit and vegetables from pests.
In addition, certain combinations of crops help to yield more than if they were planted alone, for example, mixing peas, potatoes and sweet corn.
#5: Encourage beneficial animals and insects
Don’t be too tidy in your garden. Leave or create little places where animals and birds can live, such as hedges, hollow logs, piles of stones, or nesting boxes in trees. Ponds, bird baths and other water features also attract these natural pest controllers.
Discover which plant types attract beneficial insects and plant them in your garden. For example chives and sunflowers attract bees, which are essential pollinators.
Go organic in your garden and enjoy a varied and chemical-free wildlife haven, while knowing you’re protecting SA’s soil, water and biodiversity.
Published on Jacaranda FM’s website on 2 April 2012