Answer: Ferns naturally grow in humusy woodland soils, so heavy clay is a challenge for them. Try working in some compost, either from your own household pile or purchased from a garden center. Also, be careful with the aluminum sulfate. It is probably a good idea to test the soil before you amend it. You may have had perfect soil pH for ferns and now it may be too acidic. Contact your County Extension Office (ph# 317/253-0871) for information on how to test your soil. Hope this helps!
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