Pond cleaning a huge chore — but worth the effort

The sudden appearance of spring has me scrambling to attend to chores that should have been done by now.

The lawn is showing signs of life, but I have yet to get the mower ready for the season, a task that includes sharpening the blades on a grinding wheel. Poppy seeds that I should have scattered in winter are still in their packets, so I'll have to wait and sow them next fall for blooming the following May. All those clay pots that should be scrubbed, sterilized and ready to go are still stacked in the shed, caked in old mud and fertilizer salts.

These deficits are mere trifles, however, compared with the one job that gives credence to T.S. Eliot's idea that April is the cruelest month. I refer to the periodic draining and cleaning of the fishpond. This should be done every couple of years, but I usually wait twice as long as that because it's a task whose anticipation could easily keep you up at night. It's essentially two days of messing about in bone-chilling water, fretting about the survival of your fish and dealing with gunk.

But I can speak of this with some detachment, because I undertook the task a year ago. This spring, the pond preparation is relatively easy and will consist of cleaning one submerged filter and two others that are outside the pond, and extracting four pots of mud containing the remnants of last season's tropical waterlilies. They will receive new ones in May.

Let's cut to the chase. Are ponds a lot of work? At times, yes, even when they are designed to minimize problems with water clarity and health. Are they worth it? They are; they bring a unique vitality to the garden.

After a few false starts, I decided to go big with the filtration system in the belief that it was better to over-engineer than not. The result is a large green box beside the pond, with one chamber for physical filtration and the second for biological control. In the latter, bacteria simply arrive to munch on toxic ammonia to make a kinder nitrate. The whole shebang, including a fountain, is run by a strong pump that moves many hundreds of gallons per hour. (The pond contains 2,500 gallons, which is considered mid-size as garden ponds go.)

In spite of the robust filtration system, time takes a toll: The pond gets mucky from accumulated fish waste and the decay of fallen holly blossoms, dead algae and more. You can't get rid of all this, nor of the string algae on the sides of the pond, without draining it — hence last year's spring cleaning. One of the most time-consuming aspects of the job is catching dozens of goldfish, four large koi and, because every life is precious, the tiniest mosquito fish that have multiplied over the years. They are black, hard to see, and as small and wriggly as worms. The fish spend the weekend in two large trash cans of pond water full of aquarium aerators. We are all relieved when it is over.

At the same time I replaced the ailing pump, whose high cost was tempered by the fact that it was supposed to run for seven years but lasted twice as long.

The excitement of having a fresh pump and a clean pond was also tempered by the fact that I would still be looking at the green filtration box. The pond technician said modern filtration boxes are much smaller than mine, but if I wanted one I'd also have to retrofit a skimmer to the side of the pond as well as an ultraviolet light assembly. That isn't going to happen. A landscape architect friend suggested I move the box to behind the stone wall that forms a backdrop to the pond, a measure that would require threading three pipes through the wall. I might just replace the three boxwood bushes in front of the box with bigger ones. Life is too short to wait for boxwood. But it isn't too short to think about getting this year's aquatic flora in the works, particularly the waterlilies. Hardy lilies are lovely and need less elbow room than tropicals — a consideration for small ponds — but the tropical lilies bloom day and night until the autumn, are thick with fragrance and bring a sense of exotic luxury to the clammy weeks of summer.

The presence of waterlilies has been brought into vivid relief with the release of four new postage stamps depicting lilies in various hues: blush, magenta, violet and white. They were photographed by Cindy Dyer, a photographer and graphic designer from Alexandria, Va., at the Kenilworth Aquatic Gardens in Northeast Washington.

The knack to a good waterlily photo, she told me, is to capture the bloom either on an overcast day or in the shade, using a piece of photographer's kit called a portable light diffuser. In the past, she has grown a waterlily in her own small backyard pond. “We have frogs,” she said. “Right now, it needs cleaning.”