Marianne's Response

Follow up question about using fertilizers and drip irrigation

Hi Marianne,
Thanks a lot for your kind answer about using Osmocote and drip irrigation for my fig trees and other fruit plants in 7 to 10 gallon pots. I was very confused because I was getting constrasting answers from drip irrigation suppliers: that I had to use spot-spitters or some kind of spray-type emitter that would water the fertilizer from the top, or even that it would be better to use liquid fertilizers….

I’m happy to know that my irrigation system using button emitters WILL work with Osmocote. Thanks!

I do have a follow up question on fertilizers and drip irrigation, as this is now a question on my mind and I’m very curious about other kinds of solid fertilizers, such as chemical granular fertilizers and organic fertilizers. Would these fertilizers also work when the soil is moist, or do these need to actually have water fall over them?

Thanks again for the help you have given me already, and for any further information you can give me on this matter!

Posted by Edgard Riba on July 30, 2026

Marianne's Response

Great question about granular and organic fertilizers. Solid fertilizers like the granular chemical types also need moisture to be activated but mixing it into moist soil is enough to release the nutrients. This is why they are sometimes called quick release plant foods. There is no coating on the fertilizer, so it is released as soon as it gets moisture on the granule. If the soil is just barely moist the nutrients will be only partially released. If you soak the soil the granules release and dissolve more quickly. Organic fertilizers also need some soil moisture to work but how fast or slow depends on the form of the fertilizer. Liquid seaweed is quick while composted manure can be slow (steer manure) or hot and quick (chicken manure.) The easy way to remember this all is that water moves the nutrients so the more water the quicker the release. One more reason not to let the soil dry out on your potted plants. No water means no food (or drink) for your plants. Keep growing, Marianne Binetti

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