How to Treat Nutrient Deficiencies and Toxicities
Because nutrient imbalances can be a result of an imbalance in the soil, impaired or elevated availability or problems with a plant's uptake of nutrients, to treat a nutrient imbalance you first need to ensure your plants are able to uptake nutrients properly. If you suspect a nutrient imbalance in your plants and you've done everything you can to ensure your plants are capable of taking up nutrients properly and that the availability of the nutrients in the soil is appropriate for your plants, then I would always recommend you have a laboratory test your soil before taking further action. This will enable you to make absolutely sure that the problem is due to a nutrient imbalance in the soil, preventing you from wasting money on fertilisers that you don't need and from over correcting. Some labs will also provide you with tailored advice on how best to treat any problems you discover based on what you're growing and the type of soil you have, along with other environmental factors.
Below is a general guide to treating nutrient imbalances. I would encourage you to use this in conjunction with the specific information about each nutrient that can be found on this website.
7 Steps to Treating Nutrient Imbalances
- Check the visual symptoms to determine which nutrients might be causing the problem.
- Taking a photo is also a great idea as you can more easily monitor the progress of any treatments if you don't have to rely on your memory of what the plants look like before you did anything.
- If you needed to adjust the pH, add water or improve drainage, warm the soil up (eg. using a cold frame) or move the plant to a different spot (or prune overhanging branches or add shade cloth) then wait 3-4 weeks and if symptoms haven't improved, move to step 3.
- If the soil tests show that all the nutrients are in the normal range, have some plant tissue tested. If the tissue test shows a nutrient imbalance, something else (such as a pesticide) is causing the plant to uptake an abnormal amount of nutrient and you'll need to fix that problem.
- If the test shows that the plant has the correct amount of nutrients, something else is causing the symptoms. The plant may have a disease or may have special requirements that you're not meeting (some plants need unusually acidic soil for instance).