Question
I have a few questions about plant soil. I have a few plants that are sensitive to fluoride and salt. I use filtered water to water them. I read that perlite in the soil is bad for these plants. What is a good substitute for perlite? Also I heard that Prayer Plants do well in soil made for African violets, is that true? If it is, how about other Maranta like plants like Calatheas? Would they do well too? And last, how do you keep salt levels down in soil for salt sensitive plants?

Answer
Hi Melina,

Your questions are excellent. You are very knowledgeable.

Perlite is a source of fluoride, so it is best avoided with fluoride sensitive plants. Vermiculite, styrofoam beads, and ground bark chips all add porosity to potting mixes and are good substitutes for perlite.

AV soil is fine for your Marantas and Calatheas.

Soil salts are minerals in the soil. If you are using filtered, distilled or rainwater, then this should not be a problem as long as you are not overfertilizing. I suggest not using potting mixes that have fertilizer already added. Also use peat-based soilless potting mixes rather than soil-based mixes. If you use fertilizer, use it at half strength and only during periods of vigorous plant growth.

Please let me know if any of this is unclear or if you have any additional questions.

Regards,
Will Creed, Interior Landscaper
Horticultural Help, NYC

You can E-mail me directly at: [email protected]

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