Water Gardening Spring Start
By Cyndie Thomas
Aurora, Colorado
Click images to enlarge

It is a sure sign Spring has made its return to the pond with the shimmer of sun on the water, lily pads striving to reach the surface, fish seemingly playing tag and birds making their regular visits several times a day.

Water gardening is less time intensive than many other types of gardening, but like all other types, maintenance is a must. Maintenance in spring (as early as you can stand the cold water) plays an important role in general pond health. Even the best-balanced ponds experience some alga until plants begin growth to provide shade and take up nutrients in the water. A little effort now can decrease water "greening" that may be unhealthy to pond life and just plain unsightly.

Using a pump or siphon, remove 20-30% of the pond water. Move potted plants from the pond to a shady area. Try not to stir up dirt and debris any more than necessary so the pond bottom remains visible. Using a fine mesh net, scoop along the bottom and edges to remove leaves, debris and dirt that have blown and fallen into the pond, creating a layer of muck. Remove as much of this decaying organic matter as possible, as this contributes to the growth of algae and deprives fish of needed oxygen. Leave the moss-like algae growth on the pond sides, as this has beneficial microorganisms that help balance the pond ecosystem. Remove any excess "string" or filamentous algae growing in the pond.
			Filamentous algae

Inspect mechanical equipment such as pumps, cords, filters, and tubing for damage or wear: clean and replace as needed. Assess the condition of the liner or preformed pond for possible deterioration from sun or punctures. Check the electric circuit and make sure the GFI (ground fault interrupter) is working properly. If all is well, refilling the pond can commence. Water should be trickled in from the garden hose; this will decrease any rapid temperature change that could affect fish. A dechlorinator and chloramine remover should be used at the rate specified.

Check hardy marginal (bog) plants, trim away any remaining dead foliage, divide and repot as needed. Heavy garden soil should be used to pot all water plants. Potting soil, compost, vermiculite, or perlite should not be used, as they float out and foul the water.

Hardy lilies that have grown out of their pots should be repotted. Remove dirt from the rhizome and roots by flushing with water. Using a sharp knife on a hard surface, cut off any brown and black roots and rotted (mushy) areas from the rhizome. Separate side growth "eyes" from the primary rhizome for propagation. Hardy lilies grow horizontally and should be placed against one side of the pot at a forty-five-degree angle, with the growth tip (crown) above the soil so it has room to grow across the pot.

1. Fill a two-gallon or larger pot with regular garden soil. Firmly pack soil. Place rhizome of lily with cut end at the pot edge and crown of plant toward the center of pot. Place in the soil at an approximately 45-degree angle.	2. Add dirt to cover the lower section on the rhizome. Leave the crown above soil level. Firm dirt into place.	3. Place 2-3 aquatic fertilizer tablets about two inches from rhizome and push down into the soil about one-half the depth of the soil. Fill depressions with soil. If desired, pea gravel can be put on top of soil to discourage fish from digging in the dirt.	4. Lower slowly into the pond. To encourage early growth, submerge in shallow water then move to a depth of 10-18 inches.

Fertilize marginal plants now and every 5-7 weeks through the growing season. Lilies should also be fertilized now and every 3-4 weeks, until early August. Tablet or pellet fertilizer for aquatic plants is recommended. These products provide a slow release of nutrients that plants can absorb. Plants can now be returned to their growing spots in the pond

When pond refilling is completed, filtration and circulation can be started. If a waterfall or stream is included in the circulation, watch the pond water level for several days. If the water level drops, it is likely that ground freezing and thawing has created a problem that allows water leakage.

Tropical water plants can be placed in the pond when day temperatures near 70 degrees and night temperatures do not drop below 50 degrees, usually the middle of June.

Combining these procedures with an adequate balance of water plants will allow for your enjoyment of a healthy, beautiful pond for the growing season.