Can You Use Lake Weeds to Fertilize the Garden?

Harvest

• Algaes are simple to harvest because they often float on the water's surface. Use a net to catch them and store them in a plastic bin. Weeds that grow in the soil under the water are more difficult to harvest. In very shallow water, dig them up or run a rake through them to dislodge their roots.

Use

• The simplest way to use lake weeds as a fertilizer is to add them to compost. Healthy, active compost piles are 40 to 60 percent water, so the moisture in the lake weeds will aid the decomposition process. Add algae and other lake weeds in small amounts, in conjunction with food scraps, leaves, grass clippings and other yard waste.

Benefits

• Studies on the benefits of algae as fertilizer are limited, but seaweed is often used as a fertilizer because it supplies micronutrients, such as iron and boron, as well as amino acids and growth hormones. These materials accelerate plants' growth and improve color and vigor. Algae may also contain some of these benefits. At the very least, lake weeds will add nitrogen to compost.

Cautions

• Do not add algae and other lake weeds directly to the garden. These plants often have an offensive smell and may not break down quickly because of their high moisture content. They are unattractive and messy as garden mulch.