Plants That Require Behavior Modification
All plants, like people, have distinct personalities and they are equally as varied. Some are slow and calculated; working toward a specific goal in a strict, uniform fashion (Do). Others are moderate in their approach, reaching in all directions but not in a manner that would disrupt their neighbors and with no preferred destination they feel compelled to control (Caution). A select group, on the other hand, have the need for speed; racing across vast expanses committed to overtaking everything in their path (w/Boundaries). It’s all about power with them. These traits can be admirable, but without restraint they can get too big for their britches and cause serious problems for the person in charge of plant maintenance.
Bear in mind that all living things aren’t well known for adhering to the rules. Some make their decisions based on the situation they are planted in. Add to that the fact that all plants respond differently to variations in climate, sun/shade exposure, water quality, etc. and extreme environmental trends are possible in any location. What may be the norm in a pond with a moderate fish load and adequate circulation in Florida may not be at all how that plant responds in Michigan or California under similar circumstances.
The Doctor is In
I frequently field calls from customers who have had plants used inappropriately in their garden ponds and lived to tell about it. In some cases the plants grow so fast that their garden ponds could be confused with the likes of the 1960 film – Little Shop of Horrors. All kidding aside, what these plants really need is just a little behavior modification or boundaries. Some are large with high impact foliage and deserve a place of honor in any garden pond. Others are commonly used in a majority of pond plantings. If not planted within the confines of a rigid container they may cause damage to the liner.
Often the problem lies in gravel planting pockets, which can prove detrimental since some of these plants are notorious for grabbing on to each and every pore in the gravel and never ever letting go. After extended periods of growth they will eventually need to be maintained and heavy equipment may be required because the dense growth and gravel are impermeable to modern hand tools. Rigid containers are also useful for tropical plants making them easier to extract in the winter for the northern gardener. It also prevents excessive decaying matter from remaining in the pond during the cold months.
Some of the Best and Worst
Baumea – Variegated Striped Rush is a striking rush that has rigid stems vertically striped with a splash of yellow along each narrow blade. It forms a uniform, cylindrical stand of foliage and is a favorite among gardeners and landscapers. Care should be taken when handling Baumea due to the exceptionally sharp tips at the top of the blades. Protective eyewear is encouraged. Like the leaf tips, new growth shoots are also very sharp and are capable of puncturing pond liner when planted unconfined in gravel planting pockets. It is recommended to plant in a rigid container providing ‘Boundaries’ and then nestle the container into the gravel if that is the preferred display/planting method.
Equisetum – Horsetail is one of the most characteristically unique plants found. It has been around for a few hundred million years and once established it prefers to hang around; indefinitely. If Horsetail escapes from its intended destination and permeates the soil surrounding the pond it cannot be easily eradicated and spreads rather quickly. There are no known herbicides to control it and manual removal is nearly impossible. It doesn’t mean this spectacular plant shouldn’t be used, it simply means a safe place to use it would be in a container without holes that isn’t buried in gravel or better yet in a floating island where it has zero chance of connecting with surrounding soil.
Iris – Iris should be considered for most water gardens since it is up early consuming accumulated nutrients from the winter months and offers a clear sign that spring is on the way. Iris is extremely easy to grow and requires little maintenance but recall some plants grab on to gravel and never let go. Iris may well be at the top of that list. Other than top dressing, gravel should remain the enemy of Iris. Several years of accumulated growth in a gravel planting pocket and the plant can become completely unmanageable. A rigid container will prove much easier to manage. Another consideration might be to grow Iris hydroponically. It generates a hefty root system that can easily be self-sustaining as long as it is anchored to keep it from floating away or falling over.
Nelumbo – Lotus plants will grow runners from 20´ – 60´ per season depending on the cultivar and growing conditions. Providing a substantial container without holes will easily provide the boundaries necessary to keep lotus in its place. Pond liner can also be used to build a planting area adjacent to the water garden so the lotus can have a larger, more creative growing area. 12˝ deep with 90° sides is ideal. Keep the soil level shallow (4 – 6˝) and no gravel or rocks should be used.
Nymphaea – Water Lilies prefer soil over gravel as a planting medium. Generously sized containers provide adequate soil mass providing room for growth and easy fertilization. Containers simplify the removal of tropical varieties from the pond for winter.
Orontium – Golden Club is definitely on the ‘Do’ list of plants and should be a staple in the garden pond. They can be planted in gravel pockets or containers without incident. The slow, steady, clump habited growth means this modest beauty requires very little maintenance or care. A winning plant that is underutilized because it is slow to mature.
Phragmites – Reed has extremely sharp new growth shoots that are notorious for puncturing liner. The punctured pond liner can go unnoticed for several growing seasons while the problem continues to worsen. The rigid hollow stems plug the holes in the liner temporarily. Upon eventual removal of the plant dozens of holes are opened on the pond liner sidewall. This plant should always be confined to a sturdy planting container and never used in gravel planting pockets.
Typha – Cattail, like Phragmites, have very sharp new growth tips that can puncture liner. Dwarf and medium varieties pose the same threat so all cattails should be avoided in gravel planting pockets and be kept in containers where they can mind their manners.
Zephyranthes – Rain Lily is clump habited and highly desirable. It has a modest growth habit that makes it suitable to containers, gravel planting pockets, or nestled among rocks along the streams edge. The delightful beauty is underutilized because it blooms so late in the season but the crisp white flowers are a welcome surprise in late summer.
For a complete list of Plant Do’s & Don’ts and what it all means to you, visit www.pondbizmag.com
Gravel planting pockets can complicate the long-term care and maintenance of some plants. Serious consideration should be given to the plant selection and long-term success or failure prior to execution. Alternative substrates, like calcined clay can be substituted for gravel to ease maintenance. It is lighter weight and easier to cut through than gravel so it is better suited to plants like iris that have clingy root systems.
Some landscape contractors have been successful creating planting pockets and establishing plants without any media at all. This type of hydroponic growing has huge benefits beyond regular plant maintenance. Fish fry, insects, tadpoles, bacteria, etc will all prosper in the root environment.
Landscape contractors need to be especially aware that what happens after they leave doesn’t just involve failed pumps or algae blooms. A sound knowledge of plant material is the key to satisfying customers. Plants are often overlooked and are a valuable source of revenue in the landscape plan so that knowledge won’t be going to waste. Additionally clients often feel slighted if the plant selection and planting is left to them; it is frequently perceived as an incomplete job. There are a few avid gardeners that prefer to do it themselves but that segment of the population appears to be dwindling as the do-it-yourself market shrinks. More consumers are willing to pay for your expertise. A good understanding of plants and their growing habits can prove invaluable when selecting or recommending plant choices for the water feature as well as adding to your bottom line.
About the Author
To Make Contact:
Kelly Billing, Nursery Manager
Maryland Aquatic Nurseries
3427 N. Furnace Road
Jarrettsville, MD 21084