How to Fertilize Bird's Nest Fern
When Should I Start Feeding My Bird's Nest Fern?
Begin feeding your Bird's Nest Fern when fresh new fronds start unfurling from the center rosette in spring, typically once indoor light levels increase and temperatures warm.
How Often Should I Fertilize My Bird's Nest Fern?
Once a month during spring and summer is plenty for Bird's Nest Fern. This is a slow-growing plant that does not need frequent feeding. Pushing it with more fertilizer will not speed growth, it will just cause brown frond tips.
Reduce to every 6-8 weeks in early fall, then stop completely for winter. Even though this fern stays green year-round, its growth slows dramatically in low light and it cannot process extra nutrients.
If you see brown tips on new fronds or a white crust on the soil, you have been feeding too heavily. Flush the pot with plain water and skip the next two feedings.
What Is the Best Fertilizer for Bird's Nest Fern?
A balanced liquid fertilizer (10-10-10 or 20-20-20) diluted to one-quarter strength is the safest choice for Bird's Nest Fern. Ferns are notoriously sensitive to salt buildup, and full-strength applications can scorch the fronds and damage the shallow root system.
Liquid is strongly preferred over granular or slow-release formulas. Granules can sit against the rosette center and cause rot, and slow-release pellets make it impossible to control how much the plant receives at any one time.
Avoid any fertilizer with urea as the nitrogen source, as ferns process urea poorly and it can cause tip burn. Look for formulas that list ammoniacal or nitrate nitrogen instead.