The Pond Plant Girl.com
All the water herbs grow well in partial sun and prefers still shallow water (about 10"-12") over deep or moving water. In hot dessert-like growing zones (such as zone 9-10) it is important to hang a "woven" shade cloth over the pond during the hot summer months. I am located in zone 9 and use 40% shade material. This grade cannot be purchased at the local garden center, but is very affordable at http://www.shadeclothstore.com.
All herbs can be potted in either a 1 gallon black plastic container or a ceramic terra cotta container. The best planting medium is loam; which can be made with equal parts decomposed granite (DG) and bagged steer manure. If you do not have this available, then plain clean kitty litter (with no fillers or perfumes, not litter used for oil spills) will also work well. If you have access to heavy clay soil, this is also a good choice. I do not recommend purchasing potting loam from the garden center. It is far too light weight and messy too. To prevent the soil medium from spilling out the bottom of the pots, place news paper at the bottom of the pots. It will eventually decompose, but will stay intact long enough for the soil to swell.
Only use fertilizer that is manufactured for aquatic plants. I have some excellent fertilizer in my eBay store, including fertilizer stakes that is temperature activated and lasts for 1 full year. This is far better than using fertilizer pellets or tabs, which must be applied monthly.
Water Mint grows pretty purple puff flowers and comes back each year. Use for cooking or in tea. Eliminates the pungent pond smell from decaying leaves. Helps to keep away harmful pests such as snails and slugs.
Variegated Water Celery is very hardy and comes back each year. It is also eatable and can be part of your dinner salad. Its attractive pink and green leaves rise about 4-5 inches above the water. Comes back each year. Cold Weather Pond Plant - Zone 8 and up. Plant in 5"-12" of water or in-ground as border plant. May be potted or allowed to spread as low landscaping
Pennywort is known for its medicinal properties and helping with some types of arthritis pain. The young leaves are the best and taste good alone or in a salad. Comes back each year. Very easy to grow, it can free float or be potted in river sand. Will grow and cover your pond. Makes a natural spawning environment for fish. Zone 6 and up.
Water Cress is an edible, broad leaved pond plant. Grows by spreading its roots freely from runners. Small white flowers in spring. Prefers moving water and partial shade. Excellent for use in plant filters. Comes back each year. Cold Hardy Pond Plant. Grows 1' tall. Zone 4 and Up.