Organic fruit and vegetables have now been shown to contain up to 40% more anti-oxidants, as will as higher levels of vitamins and trace minerals such as iron, copper and zinc, than non-organic fruit and vegetables. A four year study by Newcastle University, where they grew organic and Non-organic crops on the same site, has been confirmed with data from other sites in Europe. So far, the particular organic cultivation methods which produced such dramatic results, have not been reported. We always knew that organic fruit and vegetables would not be contaminated with pesticides, because we were using barrier methods or particular organisms to counter pests and diseases. It is good that the health benefits of organic food, have now been scientifically proven.
A recent report states that the amount of land growing organic cereals and vegetables in the UK, has been cut by 8.6% and 7.5%. At least those with allotments have the option of growing their own organic vegetables and fruit at minimal cost and maximum freshness.
Land dedicated to growing organic food has 30% more species of wildlife present. This will include beneficial species such as bees, ladybirds and hoverflies.
Scottish Bumblebee numbers have fallen by 60% over 50 years. Neonicotinoid pesticides are again blamed. Bumble bees fly earlier and later in the year than honey bees. On my plot, most pollination is done by bumblebees even though there are 4 hives elsewhere on the allotments. Other pollinators such as hoverflies and butterflies are also affected by the pesticides. Therefore it makes sense to avoid the use of pesticides.
Fully organic gardening is easier said than done! Some things are easily done, but some are very difficult to achieve. One additional problem is that Organic organisations keep changing the criteria for Organic gardening. Some things are allowed one year and banned the next! Many plotters are mostly organic, but will use some non-organic methods where the organic ones are felt to be inadequate.
Some of the easier things to implement for Organic growing of vegetables are:-
Annual rotation of vegetable crops. It is absolutely essential for the health of your vegetables to rotate the different groups of vegetables in a three year or even better, a four year cycle. This is the way to avoid a build-up of destructive insects and soil infections. You will get less damaged or unusable vegetables, and it is the most important method of enabling you to grow organic produce.
Choose varieties of fruit and vegetables to grow that are known to be more resistant to pests and diseases.
Try and eliminate hiding places for pests, such as slugs and snails. Get rid of all those weed and grass infested areas.
Use fine mesh netting or fleece barriers. Fine netting will prevent cabbage butterfly and bird damage on brassicas, bird damage on peas, bird damage on fruit, while fleece or very fine mesh will prevent carrot root fly.
Prevent Cabbage root fly damage on Brassicas by placing a 15 cm square of carpet underlay round the plant stem. Cut a slit in the underlay square, halfway through, to achieve this.
Use companion planting to confuse pests. Alliums are sometimes inter-cropped with carrots, to confuse carrot fly.
Encourage natural predators, such as the lady birds and their larvae, by attracting them with their favourite flowers, or providing places for them to over-winter.
Apply nematodes or larvae of natural predators for particular pests such as slugs, greenfly, white fly. These are still quite expensive to buy, and can only be used when the temperature has reached a level for the natural predators to become active.
The difficult areas for going fully organic include pesticides, fungicides and fertilisers.
Natural organic pesticides. These are usually based on soapy liquid sprays, which clog up the pests, but also tend to clog up the pores on the leaves of plants. The manufactures of these sprays advise only spraying the plants up to three times. They seem to have limited effectiveness in keeping pests at bay and if they fail to cure the problem, you will have to decide if the only option to save your crop is to take non-organic action.
Garlic sprays repel whitefly, aphids and beetles. Home-made garlic solution with 125 gm finely chopped garlic, 1 Lt water and a few drops of washing up liquid, filter and use diluted with water 10 times. Best results using fresh garlic solution.
Natural organic fungicides. 1 part whole milk in 10 parts water applied twice weekly can control powdery mildew on cucurbits (cucumbers etc).
A solution of 20 g baking powder(sodium bicarbonate) per litre water can control powdery mildew on curbits if applied when symptoms first appear. N.B. High concentrations of baking powder can damage some plants.
There are several organic fertilisers but the main one, manure, is not so readily available if you live in the city areas.
While your own compost is useful, it will not be nearly enough for your needs. For the intensive cultivation of fruit and vegetables, it will need to be supplemented with the likes of blood, fish and bone meal or hoof and horn or chicken pelleted manure. If you live by the seaside, seaweed spread on the ground makes an excellent fertiliser with many trace elements in it.
For greenhouse crops there are liquid organic fertilisers available. Some people make their own liquid fertiliser from comfrey leaves steeped in water. It smells badly and it is difficult to judge the right concentration for using it on plants. Some people use water that has had manure steeped in, but while it is good for green growth, it is not really ideal for fruiting plants.
Compost heaps are an essential way of recycling annual weeds and other vegetable rubbish, and returning the nutrients that they contain to the soil. The weeds will have a lot of your best topsoil attached to their roots, and it will be returned to your ground at the end of the composting process. On allotments, compost heaps are usually constructed of reused materials, such as timber and wire mesh. Because it can take the best part of a year to break down the vegetable matter, it is preferable to have the compost bin divided into two parts. While you are filling up one part, the other part is slowly turning into reusable and nutritious soil, and vice-versa.
Compost heaps heat up naturally during the decomposition process, and the hot temperatures helps to kill weed seeds. In wet weather, this can be helped by covering the bin to shed the rain. If the compost material is very stalky and the weather is very dry, you may need to water the compost heap. It helps to speed up the composting process if you fork out and turn the heap once.
The perennial weeds like nettles, couch grass, docks, bindweed, ground elder, and marestail, are such toughies that it is essential to keep them separate from the other weeds and give them special treatment to kill them. Never put them in the compostheap. You can leave them to dry off in the sun, and then burn them. Alternatively, put the weeds into a black bin liner, tie off the top and leave to stew in the sun for several months, or even drown them in a container for several months.
Warning. Prevent dogs getting access to compost heaps.
Compost heaps are full of rotting vegetation and this can be dangerous for dogs if they try to eat any. It is also advisable to prevent dogs eating blue cheese, mouldy or rotting food, silage or fallen fruit or nuts.
These can cause tremorgenic mycotixin poisoning. The symptoms include vomiting, tremors, muscle rigidity, rapid breathing and even convulsions which can occur from 30 minutes to three hours after ingestion. If your dog has such symptoms, seek treatment from a vet as soon as possible.
Biochar is charcoal obtained when biomass such as wood, is heated in a closed container with little or no air. The charcoal is dug into the soil and it is claimed that it improves soil fertility, improving the health and diversity of soil microbial populations, soil structure, stability, nutrient cycling, aeration, water use efficiency and disease resistance.
Pre-Columbian Amazonians are believed to have used biochar to enhance soil productivity. They produced it by smoldering agricultural waste i.e., covering burning biomass with soil in pits or trenches. European settlers called it terra preta de Indio.
Biochar trials, organised by Garden Organic and Coventry University, are presently taking place with the help of farmers, growers, gardeners, and on allotments. It will be interesting to see the results in due course.
Ponds are very useful as a suitable environment to encourage frogs, toads and newts to take up residence in the surrounding areas. They will use the pond to mate and lay their spawn, which will later hatch out as tadpoles. You may have to cover the pond with netting about 5 cm from the surface to prevent large birds from eating the tadpoles. You must ensure that there is space for the frogs to get in and out of the pond easily, even when there is netting over it.
Ponds can also be used to grow watercress, as well as ornamental plants, such as irises and water lilies.