Nitrogen gas makes up about 75% of the gas in our atmosphere. It also happens to be one of the three most important nutrients for healthy plant growth.
The three most important plant nutrients are phosphorus for strong roots, potassium for fruit and flower development and nitrogen, which promotes lush growth – large leaves and thick stems. Nitrogen is essential for producing proteins and chlorophyll and it’s very important to give plants the right amount. Sulfate Of Potash
Too little nitrogen means plants get yellow leaves and stunted growth. In a lawn, the presence of clover is an indicator there’s too little nitrogen. The older leaves on Jerry’s Cinnamon bush are nice and green but the new leaves are yellow. This indicates an absence of chlorophyll, which is what plants use to manufacture the food which allows them to grow. Jerry says, “If I don’t address this problem the new leaves will become stunted.”
Jerry recommends the organic gardeners’ holy trinity:
Jerry says that he “could use chemical fertilisers, such as sulphate of ammonia, which is a very rich source of nitrogen or a mixed fertiliser, but I choose not to use artificial forms of fertiliser. They’re so rich they can burn earthworms.” Also, chemical fertilisers can add lots of nitrogen quickly which may be lost into the soil, water and atmosphere. Organic sources of nitrogen act gently and release the nutrients slowly.
To fix his Cinnamon bush, Jerry will mulch it with compost and feed it with seaweed, at the recommended rate.”
Jerry’s also got a nitrogen problem with his sweetcorn – but this time there’s a surplus.
It’s quite common to have a nitrogen surplus in the garden. Jerry had a lot of old poultry manure which was in big lumps and he decided to work it all in when feeding the sweetcorn. He says, “Sweetcorn, bananas and citrus are really hungry crops and you’ve got to add extra nitrogen but I added too much to the sweetcorn and I’ve got rank growth.” That means the stems are long, thin and weak, and need to be staked and tied for stability.
Another negative in adding too much nitrogen is that pests like aphids, caterpillars and grasshoppers can smell it and are attracted by it.
Jerry believes there’s nothing you can do when you add too much fertiliser. “You’ve just got to allow the plants to take up what they can. A little bit of nitrogen is good, too much is bad and you can never take nitrogen away when you’ve added too much.”
Nitrogen application is a juggling act. Key tips for striking the right balance include:
The result is a lush garden, full of strong, robust plants and very few pests and diseases.
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