My ostrich ferns are turning black on the tips, black on the base, and are breaking off mid stem. Three sets of circumstance. Any thoughts on why each of these things would be happening? Thank you. Pictures attached.
Black is never a good sign. A hopeful possibility is leaf burn from over fertilization. If that could be the case, hold back on the fertilizer and leach out the soil with water. I notice too they are between hardscaping. Perhaps the soil is staying too moist.
A darker scenario is root rot. Discard the infected fronds and move healthy stems to fresh soil.
Here are the requirements for Ostrich fern:
I have never had this problem before with them. It looked like something spreading from one plant to another
Unfortunately, your photo did not come through. I am unable to address the situation, properly.
I can suggest using fungicides. This will help prevent and combat fungal infections.
Here are some articles that will help:
Is it safe to plant an ostrich fern the end of October in zone 5?
Perennials need 6 to 8 weeks to become established before harsh weather. If you take the risk, be sure to mulch heavily.