Nitrogen is extremely important to a plant, being one of the macro elements (the “N” in NPK). It is involved in a vast number of process and structures with plants that a deficiency can cause serious issues with growth and development. Nitrogen plays a role in the formation of chlorophyll, vitamins, hormones and DNA. It also supports enzyme reactions and plant metabolism which maintains growth and health.

Plants usually absorb nitrogen as nitrates or ammonium but can also be taken up via tiny organic molecules. Plants need a good balance between sources of nitrogen as one is acidic and one is alkaline. Too much ammonium, for example will raise the pH around the rootzone and block the absorption of other elements. Plants with a plentiful supply of nitrates have a higher organic acid content which can affect taste and shelf life after harvest. In general, plants with a steady supply of nitrogen get bigger leaves, more branches and a stronger vegetative phase.

Nitrogen Deficiency

Telltale signs of nitrogen deficiency are important to spot and are more likely during a vigorous growth stage. The leaf stalks of plants may begin to turn purple, but most growers notice the changes in the actual leaves. Lower leaves will begin to turn yellow across the whole surface, eventually becoming white, withering and falling off. As the deficiency progresses, leaves further up the plant are affected, becoming a lighter green colour. You may notice purple stripes on the plant stem giving a further indication of the issue.

Plants that are not treated suffer badly due to a lack of nitrogen. The leaves are where energy and sugars are produced that power growth and fruit production. Plants can be forced into early flowering which will be ineffective as there isn’t much left to fuel growth. The end result is, naturally, a disastrous reduction in yield (if there is any yield at all).

Causes and remedies for nitrogen deficiency

It is an unfortunate fact that plants cannot absorb nitrogen from the air, despite it being 78% of Earths atmosphere. As it is fairly unreactive, nitrogen needs to be absorbed by the roots as nitrates and the like. Most decent plant feeds contain a good dose of nitrogen compounds, especially grow phase versions, but it isn’t always enough. A high number of micro organisms in soil can bind nitrogen, making it unavailable. Also, plants that are growing quickly are using up large amounts of nitrogen; perhaps more than the feed can supply. So how do you deal with a lack of nitrogen?

Solutions can be as simple as raising the EC of the nutrient mix you are using. While this often works, you are also increasing all the other available elements. Probably the best method is to add a specific nitrogen additive that won’t raise levels of other elements. You can also use urea, blood meal or semi liquid manure to help.

What is available from Straight Up Hydroponics for treating a lack of nitrogen?

If you’re looking for nitrogen additives, we stock a few ready to go and there are more available to order in if you’d prefer. Products we usually have on the shelf include Canna Mono N17% and RAW Nitrogen. Azos from Xtreme Gardening is a beneficial, nitrogen fixing bacteria that is perfect for cuttings and seedlings. These are all under “Additives” on our website and you can go there by clicking here. You can see all the nitrogen products available by selecting “Products” and typing “Nitrogen” into the search bar (for mobile devices) or just typing it in at the top of the page on desktop computers.