Q.What Is A Good Fertilizer For A Potted Olive Tree?
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Certified GKH Gardening Expert
They grow in, naturally, poor and dry soils. I would not fertilize them.
Likely, the potting soil that you plant them into will contain more than enough fertilizer to last them for many years.
Should a soil test show extreme deficiency, then you can top dress with compost.
Here are some articles that will help:
https://www.gardeningknowhow.com/edible/fruits/olive/olive-tree-care-information.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/test-soil-for-pests-and-diseases.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/making-sure-soil-drains-well.htm