How to Use Seaweed & Kelp in a Garden

Seaweed can be found near the water's edge at beaches and lakes.

Seaweed fertilizer has been used in agricultural production for centuries and is often used by environmentally conscious gardeners as a natural way to improve soil quality. Any type of seaweed, such as kelp, can be used as a powerful organic mulch. It contains more than 70 enzymes, vitamins and minerals, and it nourishes the soil as it breaks down. Using seaweed and kelp in your garden also reduces soil erosion, helps control weeds and provides the plant with increased resistance to diseases.

Things You'll Need

• Hose
• Garden shears

Instructions

1. Collect fresh seaweed from a nearby large body of water, such as a beach or a lake.

2. Spread the seaweed out on a flat surface in thin layers. Use a hose to rinse it thoroughly to remove as much of the salt as possible. Hose for one hour per inch of depth.

3. Chop the seaweed into small sections, around 2 inches in length, using garden shears. Get rid of any debris caught up in the seaweed.

4. Place layers of the seaweed, no deeper than 4 inches, around and in between your plants. You will know if your layers are too thick because water will not get to the soil and your plants will become dry.

5. Add more seaweed mulch when the layer breaks down to less than 2 inches.

6. Add seaweed to your compost pile to aid decomposition and contribute important nutrients.

Tips & Warnings

• Restrict your seaweed use to plants that are not sensitive to salt; even though you have given the seaweed a thorough hosing, some salt will remain.

References

• University of Florida IFAS Extension: Caring for Plants
• Plantea.com: Help from Kelp