Cactus fertilizer ratios

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RichR
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Cactus fertilizer ratios

Post by RichR »

Have read in a number of places that a fertilizer with a high ratio of phosphorus 1-2-1, 1-3-1 or something to that effect, is desirable for cacti.

John Trager advocates use of a 12-5-5 and Cactus Specialties in California uses a 15-5-15 cal-mag. I was under the impression that a fertilizer with a high nitrogen ratio led to soft, flabby growth and discouraged flowering.

Yet I'm certainly not in a position to question Trager, so what's the reality?
iann
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Post by iann »

You can do any or all of these depending on your other cultivation methods. If you have a giant open-air growing area in the desert, you can follow John Trager, If you have a set of t9iny pots inside your house maybe you would work differently. Different soils and different watering techniques also required different fertilisers.

My recommendation would be little (very little!) and often, and make sure you have trace elements if you grow in a pot. You are unlikely to starve a cactus of nutrients in any short period of time so don't panic about it until you have more experience. As with water, less is more, but none is not enough. I just made that up :)
--ian
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CoronaCactus
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Post by CoronaCactus »

Also keep in mind the HBG grows a majority of their plants in pure pumice or in a mix with a very high percentage of pumice.
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RichR
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Post by RichR »

If I'm not mistaken, doesn't DG contain most trace elements?
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