LSU AgCenter's Weekly Message

Working with Wet Areas on Your Land

Last week’s rains – about 5 inches in two days at my house – provided a good chance to observe where water accumulates in our yards, on our fields, and in our woods.

There are ways to improve drainage in some places. Sometimes it may be as simple as cleaning out a ditch so that water has a place to go. Grading and French drains are options in some situations.

In a lot of cases, though, it’s more practical to just work with the conditions you have. This goes along with the “right plant, right place” principle, or matching the plant to the site.

While some plants cannot tolerate even short periods of standing water or saturated soil, there are quite a few plants suited to wet areas.

Some herbaceous (non-woody) plants for wet areas include carpetgrass (Axonopus fissifolius), Virginia blue flag iris (Iris virginica), Louisiana irises (giant blue iris [I. giganticaerulea], zigzag iris [I. brevicaulis], dixie iris [I. hexagona], copper iris [I. fulva], Abbeville iris [Iris x nelsonii], and hybrids of these), southern swamp lily (Crinum americanum), swamp spider lily (Hymenocallis liriosme), Texas star hibiscus or scarlet rose-mallow (Hibiscus coccineus), crimsoneyed rosemallow or swamp rose-mallow (Hibiscus moscheutos), common or soft rush (Juncus effusus), and needlegrass rush or black needlerush (J. roemerianus).

Some trees and shrubs for wet areas include bald cypress (Taxodium distichum), pond cypress (T. ascendens or T. distichum var. imbricarium), nuttall oak (Quercus texana, formerly Q. nuttallii), water oak (Q. nigra), black gum or tupelo (Nyssa sylvatica), swamp tupelo (N. biflora), water tupelo (N. aquatica), Drummond or swamp red maple (Acer rubrum var. drummondii), river birch (Betula nigra), parsley hawthorn (Crataegus marshallii), mayhaws (Crataegus opaca and other Crataegus species), common persimmon (Diospyros virginiana), sweet bay magnolia (Magnolia virginiana), wax myrtle (Myrica cerifera or Morella cerifera), titi (Cyrilla racemiflora), Florida anise (Illicium floridanum), American holly (Ilex opaca), dahoon holly (I. cassine), possumhaw (I. decidua), winterberry holly (I. verticillata), buttonbush (Cephalanthus occidentalis), and Virginia willow or sweetspire (Itea virginica).

The plants I mention here are just some examples. One way to get an idea of whether a plant is suited to wet areas is to check a resource such as the US Department of Agriculture Plants database (https://plants.usda.gov/), the US Geological Survey Plants of Louisiana website (https://warcapps.usgs.gov/PlantID/), or the LSU’s Louisiana Plant Identification and Interactive Ecosystem Virtual Tours site (http://www.rnr.lsu.edu/plantid/) and look at the wetland status of the plant. Plants rated as OBL, or obligate wetland plants, are almost always found in wetlands. Those rated as FACW, or facultative wetland plants, are usually found in wetlands, and those rated as FAC, or facultative plants, are found in both wetlands and non-wetlands. Those least likely to be suited to wet areas are the UPL, or upland, plants which are rarely found in wetlands.

Be sure to also take other factors, like the expected mature size of the plant and how much sun or shade it needs, when making plant choices.

Let me know if you have questions.

Click here for previous LSU AgCenter's Weekly Messages

Dr. Mary Helen Ferguson is an Extension Agent with the LSU AgCenter, with horticulture responsibilities in Washington and Tangipahoa Parishes. Contact Mary Helen at mhferguson@agcenter.lsu.edu or 985-277-1850 (Hammond) or 985-839-7855 (Franklinton).