(Don't get this plant....this plant BAD!) Thanks, "Little Shop of Horrors".
Plants are vital! If you choose to have no plants in your pond or watergarden, you will spend a great deal of your time (and a whole bunch of money) keeping the pond clean and clear. Plants elevate your pond's habitat and improve its filtering capacity. Aquatic plants are your most efficient filter for most any aquatic environment. They are working 24hrs a day and (if you choose correctly) will wake up every spring to begin the fight again.
What fight, you say?
Why, the fight for ecological supremacy! The only true battle of value any self-respecting freshwater steward may undertake in the long struggle of pond ownership.
I can help!
Here are a few plants to get you started. I have added descriptions and some comments for where/how to plant them into your pond.
Pond Lilies (many genra and species available):
These plants come in a wide variety of colors and are very versatile. Most can grow in as little as 6in of water, and some can thrive in up to 8-10 ft of water depth. Our native lilies here in the upper Midwest are white and yellow and can sometimes grow out of control if left unchecked. I therefore recommend the cultivars that are not from around here and that tend to grow more slowly. My advice in selecting your pond lily is to check out your local nursery and see what's available and/or peruse the selection that online growers offer. Make sure to select varieties that are hardy to your region so that you can enjoy the plants next year as well.
There are tropical pond lilies that have wild colors and some that bloom at night (SUPER COOL). These lilies will have to be either boarded over the winter inside your home or treated as annual plants in your pond.
Arrowhead (sagittaria latifolia, and others):
These are my favorite! These are native aquatic plants that grow in water from 6-8 inches of depth all the way to above the waterline in wet soil, and range from 14-24 inches in height. Arrowhead reproduces mainly by tuber. They produce a marble to golfball sized starchy "potato" that resides under the soil line. These tubers are edible too (though they do not taste very good), and are the most nutritious aquatic plant that is native to our area. "Why is nutritional value important?", you ask. Arrowhead is the most efficient filter of nutrients in our aquatic environment. It sequesters more nutrients per unit mass than any other aquatic plant native to the Midwest. Deer, rabbits, geese, ducks, and muskrats will gladly dine on these guys whenever they get the chance. You will have to protect new plantings, but once they become established, they will be able to survive a certain amount of herbivory.
I get the best success planting Arrowhead in soil. They prefer highly organic media, but I find that they do just fine in whatever soil is present in your natural pond. If you are planting them in a watergarden or koi pond, make sure they have 4-6 inches of pea gravel in which to grow. You can also sink a pot in 6-8 inches of water with pea gravel mixed with a small amount of peat moss.
Expect these wonderful plants to spread themselves out in your pond, as the tubers float. These plants also produce flowers...and therefore seeds...so you may get some reproduction through the spread of the seeds as well. If they land somewhere they are not wanted, they are easily transplanted or pulled out.
Blue Flag Iris (iris versicolor):
Ok, these are my favorite! A native flower, Blue Flag Iris stands from 24-36in tall with long slender lunate (or spear-like) leaves. It will grow in water 4in deep to damp soil. This iris (like most irises) blossoms in spring, exhibiting the delicate blue flowers you see above (Blue Flag will bloom more in full sun, but does not require full sun to grow). I love this species for its robust nature and great habitat potential for the pond's edge. Clean it up in the fall by cutting down the foliage, and wait for spring. Every 3-5 years you can split the clump to encourage new growth.
Other aquatic irises (like Yellow Iris or pseudacorus) are also great. Most states have them listed on their invasive species lists due to their ability to spread into native waters. They grow and spread readily by seed, and I must admit they are non-native, so that is a concern to all of us looking for a groovy natural landscape. BUT!!!!!! If you promise to keep them confined to your pond, I won't tell anybody. They grow larger than the Blue Flag and produce more blossoms in the spring, subsequently producing abundant seed pods. To control the spread, just clip off the seed pods as they form and you're in good shape.
Soft Rush ( juncos effusus):
Ok... These are my FAVORITE! Soft Rush is the coolest! It grows spiky dense clumps about two feet tall and it is awesome. Soft Rush grows slowly by adding several new spikes every year, slowly expanding the clump of awesome. This is a versatile plant that will grow in 2 inches of water, but prefers living at the waterline. Soft Rush can be divided at any time. It is also excellent habitat for the insects, birds and amphibians that frequent your pond.
Alright...... These will get you going. there are MANY more species out there that are suitable for your pond. I try to keep these articles short so you all come back to read another one. ;) I will describe many more aquatic plants in subsequent articles, so stay tuned. If you have questions or comments, please ask in the comments section. Thanks for taking the time, and get out there and enhance your pond with some plants!