Many of the species that make up meadows are actually considered medium water use plants. Many grasses and perennial wildflowers thrive in wet environments. These plants have roots that will grow deep into the soil. They may need more water than more drought tolerant plants, or to be watered more frequently, or to be watered more continually to keep looking green and healthy.
A perfect source of water for water wise or native meadows is rainwater diverted into a constructed vernal pool.
“Vernal pools, or seasonal pools, are a unique type of wetland habitat. They are typically small, shallow, ephemeral water bodies, and unlike a pond or a lake, they have no permanent inlet or outlet. They are filled each spring by rain and snow melt, then dry up for a period of time during the summer.” http://www.naturalheritage.state.pa.us/VernalPools.aspx
Constructed vernal pools are a type of earthwork that typically have a wide flat bottom, and a depth of just 1-3 inches. Rainwater can be diverted from a downspout into the pool, so that it fills evenly during a 1” rain. Once filled, excess water can be directed out of the vernal pool using an overflow that is just lower than the inlet, or it can overflow on all sides. The rainwater will usually infiltrate within 24 hours or less, and in the meantime, the plants that are fine with ‘wet feet’ will rejoice in the water.
As with any earthwork, the additional rainwater directed into a specific landscape area not only provides the plants with an abundance of water during the rainy season, it helps to transform the soil into a biologically rich sponge, where over time, infiltration will increase between 40-90%. Typically, and especially after establishment, plants in this environment won’t need to be watered in the spring for an additional month or two after the rains have stopped. Depending on the plants selected, they may continue to not want water during the summer months.
The time to plant such a meadow is in the fall or early in the rainy season. The vernal pool can be constructed anytime during the year.
Stunning and sustainable, with an innovative water source- a water wise meadow in a vernal pool may be just the water feature you’re looking for in your own back (or front) yard.