There is growing awareness about the value of preserving and restoring native plant habitats for the benefit of wildlife, especially our native pollinators. The increase in demand for native plants has led to the selection and breeding of native cultivars.
What is a native cultivar? A native cultivar or “nativar” is a cultivated variety of a native plant that has been selected, cross-bred, and/or hybridized by plant breeders seeking desirable characteristics – usually height, bloom color, bloom size, leaf color, and even disease or pest resistance.
Should you be using native plant cultivars? Are they as robust or as beneficial to wildlife as straight species natives? What exactly is a straight species?
There is an emerging debate over whether cultivars provide the same ecosystem services as the native species themselves. The research seems to be unclear when comparing the two because not all cultivars are created equal – some are better, some are the same, and some are worse at attracting pollinators; it really depends on the plant species and its cultivar.
So how do you know if a cultivar is good or bad? Unfortunately, it’s hard to tell and you must do your own research on what the plant was bred for.
Truly native Echinacea purpurea, is a key species for pollinators. Photo by Donna Legare
Double blooming flowers are a no-go as they prohibit pollinators from accessing the pollen or nectar. If they’ve been cultivated to change the flower color, they are almost certainly going to be less attractive than the straight species.
However, if their cultivated trait is just a larger flower or shorter growth habit, they may be OK. The bottom line is that when you can get your hands on the straight species, you’re always going to have the best possible plant for pollinators.
Renowned entomologist and native plant advocate Doug Tallamy says “the proliferation of cultivars demonstrates the extent to which the nursery trade is still stuck on the idea of plants as enhanced decoration rather than essential to wildlife. Always request true native plants because there is only a market for cultivars if we buy them.”
Another word of caution on native cultivars that is often overlooked is that they lack genetic variation. Their DNA is the result of artificial rather than natural selection and they present a vulnerability if a particular disease or pest becomes problematic. Without genetic diversity, there is less built-in resilience in our landscapes.
Once the genetic material from cultivars makes it into wild populations, there is no way to dispose of it. The new DNA affects the ability of wild native plants to survive and has ramifications for all the species that interact with the plant as well.
When native plants in our yards are straight species, their DNA can make a positive contribution to the survival of wild plant populations. The adaptive genetic diversity they share allows native species to persist, despite the rapidly changing conditions of the environment they are in.
Finding locally grown straight species is key to supporting local ecosystems. It’s like getting to know where your food comes from – learning where your plants come from increases transparency and the quality of information along the supply chain.