Green thumb
Beat the inflation genie and create your own fertiliser
The price of fertiliser has jumped by more than 30 per cent and is expected to increase further in the coming months. Is there a better and more natural way to provide garden plants with nutrients?
LEGUMES
Nature always provides a way and has given us plant legumes that have the ability to take nitrogen from the air and convert it into organic nitrogen.
This natural nitrogen breaks down, with the help of microorganisms, slowly in the soil and is available to a rotational crop.
To achieve this benefit, plant a legume such as dwarf beans in a garden bed. These beans crop early and have a short cropping life, dig them into the garden bed when the crop is finished.
It will take about six weeks for the beans to break down and allow the nitrogen to be available to the next crop.
This process is particularly suitable when you follow the planting with a high nitrogen requiring crop such as corn.
Each legume requires a specific type of Rhizobium bacteria, if your soil is depleted and lacks organic matter it is likely to be deficient in many of the microorganisms needed to support Rhizobium bacteria.
You can however, purchase legume seeds, from organic outlets, with the strain of bacteria necessary to form nitrogen fixing nodules on the roots of the specific plant as it develops.
COMPOST
The other tool in the garden’s belt is well made compost that is sweet smelling of a crumbly texture and has a pH of around 6.5, it is the perfect companion to improve garden soil.
Compost also reduces household waste by converting it to a valuable resource.
Use kitchen scraps, fallen leaves, old paper, lawn clippings and any organic matter that will decompose; these are all valuable ingredients and once you have the compost bug will never be put in the green bin again.
Compost alone is low in the three main nutrients, nitrogen (N), phosphorus (P) and potassium (K) but is high in carbon, micronutrients, trace elements and microorganisms. Compost added to garden soil improves the structure of the soil and its ability to hold water in long dry periods.
Conversely compost aids the water absorbent nature of the soil and absorbs and holds water in heavy downpours, thus minimising run-off and reducing nutrient loss.
The best way to use compost is to add a third by volume to a garden bed and incorporate it into the soil. Dust the soil with one cup of dolomite, or crushed eggshell dust, per square metre and leave for a week before planting.
MULCH
There are many types of mulch available to the home gardener, but the best advice is to always take a leaf out of nature’s book and mulch with leaves. When a leaf falls to the ground it’s immediately colonised by mycelium and microorganisms. The leaf is an essential part of the closed nutrient cycle of the forest.
Leaf mulch in a garden plays many roles, it protects the soil from heavy rain and prevents run-off, it acts like an umbrella over the soil keeping the roots of the plants cool, it inhibits weed seed germination, (the leaves on many trees have allopathic properties which prevents the germination and growth of weed seedlings).
Leaves also retains soil moisture and provide a food source for worms who recycle the leaf mulch into a nutrient rich form available to plants.
HOME MADE
It’s surprising how easy it is to make fertiliser at home from household waste. Egg shells contain calcium which is important for strong, healthy, plant growth. Save the egg shells, they are easy to dry in the latent heat of an oven, grind into dust and incorporate into the soil.
Banana peels contain potassium, phosphorus, magnesium and calcium. Dry the banana peels and grind into a dust.
Onion peels contain nitrogen phosphorus, iron magnesium and copper. Dry the onion peels and grind into a dust.
Fish bones contain nitrogen, phosphorus and calcium. Dry the fish bones in the oven then grind them into a powder.
Fit a large bucket with a mosquito proof netting then fill with water. Add the egg shell, banana, onion peel and fish bone powder to the water, stir well. Place the bucket in a cool position under a tree. Stir the mixture every day making sure the mosquito netting is fitted tightly. The brew will be ready to use in two weeks.
Strain one cup of the brew and add to five litres of water and use it as a drench around seedlings or use as a foliar spray on more mature plants.
The organic fertiliser brew should be used in conjunction with green manure rotation as well as the incorporation of compost and leaf mulch soil covering.