I always knew Boston ferns (Nephrolepis exalta) were special. I've had a soft spot for these tropical beauties since spending a mild winter in Georgia. My landlady had the greenest, most enormous ferns I'd ever seen on the porch of her rambling southern home. When I got married that spring, she brought them to help decorate the chapel. They filled her car, adding another over-the-top element to an outstandingly beautiful day.
My grandmother had a much-complimented Boston fern at the farmhouse where my mom grew up. Every fall, it was brought inside, and my mother had the unenviable job of picking off all its browned fronds. In spring, it was cut back hard, and its pot was replenished with the richest compost that could be scratched up, one handful at a time, from beneath big trees in the woods. Two weeks later, it would be huge and lush, ready to hang on the front porch for all to enjoy.
Grandma loved roses best of all, but my mom will choose a pretty fern over a rose any day. I picked up an enormous Boston fern for her last spring. Yellowing outer leaves had it marked down to $10, but I knew it just needed a helping hand. The fern was so tightly rootbound that it could no longer absorb moisture. Water just ran right through the pot.
Remembering how Grandma's potted fern had been refreshed every year, I knocked off as much old soil as I could to make room for fresh potting mix. I loosened the roots and pruned back a few of the longest ones. When we brought it up a week later for Mother's Day, it was bursting with healthy new growth.
Ferns love water, so I put an extra tablespoon of polymer moisture crystals into the bottom of the hanging basket. The hanging container I chose has a self-watering bottom. Dad had no trouble keeping Mom's fern well watered by refilling the saucer reservoir every couple of days. When "his" Carolina Wrens started looking at the fern as a nesting site, he was even happier to be able to water it from below!
They've had ferns on the back porch before. Usually they look pretty tired and beat-up by the end of summer, and Dad sneaks them into the compost pile. This one just got larger and prettier all summer, though, so Mom made sure it came in before the first freeze. They asked me to over-winter it for them. I looked around my crowded window areas and wondered where I'd find a place for such a big plant. Then my friend Sharon gave me great advice: Don't wait until spring to cut it back!
I gave that fern the haircut of its life, taking all those green fronds down to two inch stubs. Seeing some small new fronds emerging between all those chopped ends gave me hope that I hadn't killed it with such extreme pruning. I put it in a north window for partial sun and gave it enough water to keep it going. By Mother's Day, I hoped it could resume its pride of place on my parents' back porch. (Unfortunately, I forgot to water it once too often, but I'll try again with this year's fern!)
Pruning a Boston Fern way back in fall means far less space is needed for over-wintering. It will gradually put out new growth, but it won't grow out as quickly during winter as it would after a spring trim. By spring, the foliage will be large and full again.
As with any plant kept indoors, introduce it gradually to outside conditions. Those tender indoor stems need to toughen up and be hardened off before the plant can be out all day. If a spring frost threatens, be sure to bring it back inside for the night.
Boston ferns are easy growers if you're willing to do the "in and out dance" with them as the seasons change. With annual pruning, the plant will renew itself for many years, providing a striking focal point in both winter and summer. Reserve a place for this cool, green beauty, and listen to the compliments roll in!
Photos by Jill M Nicolaus. "Mouse over" images and links for more information.