Native Plants and Wildlife Conservation: Why Your Yard Matters More Than You Think
Native plants save our wildlife because they are the only food that many native insects and animals are equipped to eat․ A monarch caterpillar cannot eat a Bradford pear leaf․ The mining bee can't dig its nest underneath English ivy․ When you plant native species that have co-evolved here in Tennessee with our birds‚ bees‚ and butterflies‚ you recreate a food web that ornamental exotics simply cannot replicate․
As Doug Tallamy‚ an entomologist‚ has noted‚ your native oak tree do support over 500 species of caterpillar‚ while there are about five species on a non-native ginkgo‚ planted everywhere in suburban yards․ And that empty space is the whole point․ These species are also being replaced by non-native plants‚ which means there are no native caterpillars to feed baby songbirds when their eggs are laid (e․g․‚ 6‚000 to 9‚000 caterpillars are needed to feed a single clutch of chickadees)․
What Native Actually Means for Tennessee Gardeners
Since Tennessee is a long state east-west‚ its USDA hardiness zones range from 6a to 8a․ Cold temperatures in the Smokies occur at higher elevations‚ while the Memphis and western valley areas have a warmer climate․ A plant native to the Southeast has typically spent thousands of years adapting to our clay soils‚ humid summers and freeze-thaw winters․ That means less watering‚ no fertilizer‚ and none of the fungal disease problems that plague plants shipped in from other climates․
It also means better timing: native perennials here tend to break dormancy in March‚ flower on a schedule that local pollinators already know‚ and produce seeds just when migrating birds need extra calories․ The minute you plant something from elsewhere‚ all that goes out the window‚ though the plant may be perfectly happy․
Five Native Plants You Should Know
Larkspur (Delphinium exaltatum) is between 2 and 4 ft and grows with blue-purple flowers in spikes from June to July․ It grows in soil that drains well and in full sunlight to light shade․ Larkspur attracts a good number of bumblebees and hummingbirds‚ especially in the summer months when there are fewer flowers to visit․ It is not aggressive‚ but give it room to reseed since it likes to keep spreading a little each year․
Actaea racemosa (Black Cohosh sometimes still marketed under the old name Cimicifuga) puts up 4 to 6 foot wand like white flower spikes in late summer in deep shade to part shade in constantly moist rich soil (think of the edge of a woodland rather than an open bed)․ In customary medicine‚ it is known to host the spring azure butterfly․ Its late flowering time‚ July to September‚ is important‚ as at that time‚ most of the spring flowers are completed flowering․
One of the strangest looking native plants of the forest floor is Jack-in-the-Pulpit (Arisaema triphyllum)‚ which has a green spathe and purple spadix․ It grows in deep shade and humus and emerges in the month of April․ It can produce a dense cluster of crimson red berries by fall‚ on which wood thrush and other birds depend to survive․ In the right environment‚ the plant can survive for decades․
The life cycle of the evening primrose (Oenothera biennis) opens pale yellow flowers at dusk and closes them by mid-morning․ By this adaptation to coincide with the activity of sphinx moths and other nocturnal pollinators and selecting for compatible colors‚ evolution has made them the right color at the right time․ Better adapted to poor‚ dry soil and full sun than almost any other plant on the list‚ it is ideal for use in a hot‚ exposed position where little else would flourish․
Foamflower Tiarella cordifolia (6-12 in․ (15-30 cm) tall) is a low woodland plant that produces panicles of white or pale-pink flowers in spring above heart-shaped semi-evergreen foliage․ It spreads by stolons and is ideal for shaded‚ moist beds and as an under-tree groundcover where grass does not grow․ Native mining bees use it as an early season nectar source‚ and the leaves may color up in winter in the warmer parts of the state․
Two More Worth Adding
If you're building out a fuller habitat‚ consider Serviceberry (Amelanchier)․
