5

I live in an apartment building, and all my plants grow in pots or small flower beds. Since I moved here, 7 years ago, I have only watered the pots and revolved the "soil", eventually adding more vegetable compost to fill the pots.

I believe that a splash of NPK fertilizer would be good, but I am concerned about poisoning the plants. Is there a possibility to overdo the amount of such nutrients? What kind of damage could happen?

  • I'd ask what plants you're growing, whether they're edibles or not for one thing, difficult to give an answer without that info. At the moment, seems like the risk of overdosing on NPK fertiliser is nil, given you're not using any at all. You also haven't reported any problems with the plants - are there any? – Bamboo Sep 4 '14 at 15:49
  • There are edibles (sage, parsley, rosemary, lemongrass, lime - a small tree) and decorative plants (lavender, geranium). No issues with the plants to be reported, but they could look more strong. – Morts Sep 5 '14 at 20:27
6

Yes excess NPK can damage plants, although how much N, P, or K is too much depends on the plant.

For example, you shouldn't add too much N to the soil for radishes and carrots because that will causes them to grow lots of leaves and small vegetables. Conversely, grass-type plants, like corn, and vegetables you grow for their leaves, like kale and lettuce, will use a ton of Nitrogen.

For general knowledge, I recommend you read all the questions tagged .

  • 1
    Yes. Plus, you can burn roots with too high a concentration of fertilizer, especially nitrogen. As long as the plants in question are regarded properly, and the fertilizer instructions are followed carefully, there shouldn't be any problems. – J. Musser Sep 3 '14 at 21:02
  • 1
    And if you live in the right areas, Potassium can build up and poison plants. So don't just apply a supposedly balanced fertilizer and not test your soil. You may find that it's balance is terribly askew as your production falls off from blindly applying it. – Fiasco Labs Sep 4 '14 at 1:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.