Answer: Without actually seeing your fern and the site, I can't say for sure what the problem is, but I would err on the side of "too dry." These ferns need a woodsy, humusy soil that drains well but can retain moisture (like a well-wrung sponge). They should be watered if the soil is dry to 3" deep and benefit from high humidity around the trunk and under the canopy. It is normal for them to drop their oldest fronds every few months.
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