How to Prevent Nutrient Imbalances
Often the best defence is a good offence and nutrient imbalances are no exception to this. The best treatment for a nutrient toxicity or deficiency is to prevent it from ever occurring.
Preventing Nutrient Deficiencies
Nutrient deficiencies often occur when soil is neglected. Whether you're a gardener or a farmer, you can look after your soil by preventing soil compaction and replacing any nutrients that are removed.
To prevent soil compaction, you need to ensure you don't walk on your beds and that heavy machinery doesn't run over your beds. To do this, make sure you have well defined paths. Also, rain can compact bare soil so make sure your soil is always either growing plants (this includes green manure crops) or is well mulched.
If plant matter is being removed from the soil, through harvesting of flowers, food or other plant products, then the nutrients that are removed in the process need to be replaced, preferably by adding organic matter to the soil. Organic matter may be plant waste, compost, manure or anything else that was once living.
Different plant species require different amounts of each nutrient so companion planting and crop rotation are also important tools for preventing nutrient deficiencies. It's also important to note that while pesticides don't generally remove nutrients from the soil, glyphosphate and other similar pesticides work by preventing the uptake of nutrients by plants and it can be difficult to prevent plants from being contaminated with pesticides when they're being used on nearby weeds or insect pests. Not using such pesticides is a sure way to stop them from causing nutrient deficiencies though.
Preventing Nutrient Toxicities
Under normal circumstances, nutrients typically only build up in the soil to the point of causing toxic effects in plants, when they're added to the soil by humans. Inappropriate use of fertilisers is one obvious way nutrients may be added to the soil but nearby mining and heavy traffic can increase the amount of some nutrients in the soil and can also introduce toxic contaminants to the soil. What some people don't realise is that some pesticides, even those allowed in organic gardens, can also cause nutrient toxicities. Copper based fungicides for instance can cause toxic levels of copper to build up in the soil. If you really need to use a pesticide on your property, make sure you read the instructions carefully and research the possible side effects of the product before you use it so that you can prevent these sorts of side effects.