Water Resources | Tampa FL - WRA Engineering

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Florida Wetland Mitigation and Natural Area Plantings

(Planning, Timing, & Seasonal Variations)

The summer rainy season is approaching, so now is the ideal time to enhance your Florida wetland mitigation areas. Wetland systems in central and south Florida are typically dry or holding a small amount of water, which are ideal conditions to treat (either mechanically or with herbicide) invasive or exotic groundcover. In addition, the low water levels make planting groundcover, shrubs and trees easier. If you plan to plant wetland vegetation before the end of June, you may need to closely track daily rainfall
and incorporate temporary irrigation until our region gets it’s typical daily rainfall events.
Although Florida has a nearly year-round growing season, seasonal variations should be considered
when planning for wetland and natural area plantings. Seasonal and regional variations can play
significant role in the success of a planting and selecting the right time to plant may result in substantial
savings in time and overall cost of a project.

Much of the vegetation species utilized for groundcover establishment in wetland and natural areas are
perennial species that are planted from small containers grown in nursery conditions or transplanted as
bareroot vegetation. Perennial plants are species that persist for several years, usually with new
herbaceous growth from a part that survives from growing season to growing season. As such, these
perennial species have adapted strategies to stay alive during the changing seasons. Many of Florida’s
native emergent plant species undergo a state of dormancy during the fall and early-winter season. This
is an adaptive feature of many plants that prepares them for colder and dryer conditions. During this
dormancy period; leaf and root growth is significantly reduced or stopped.
Planting small containerized vegetation or transplanting bareroot vegetation can put a considerable
amount of stress on the planted material even under optimal conditions. Planting vegetation during a
dormancy period, coupled with the typical stress associated with planting small container or bareroot
material, may result is high degree of initial mortality. Individuals that do survive the initial planting and
grow-in period may struggle to rebound during the spring growing season and often are likely to be
overgrown by emerging exotic vegetation.

When planning for wetland and natural area plantings it is generally best to schedule the material
installation in the late spring and early summer. During the spring growing season root production is at
its most active and the summer rainy season ensures adequate soil hydration for root establishment and
nutrient uptake.

Failed plantings can result in significant project setbacks and expenses. Beyond the cost of having to
plant a second or third time, additional expenses may result from but are not limited to; increased
herbicidal maintenance to manage recruiting exotic vegetation, increased monitoring and reporting
periods, erosion of unstabilized soils, and additional contractor/agency coordination. Planning a
project’s wetland and natural area planting with consideration to these seasonal adaptations can
prevent unnecessary losses in time, additional expenses, and hassle with establishing these natural
communities.