Purple Amaranth: The Uninvited Garden Guest You Should Know About
If you’ve ever noticed small, weedy-looking plants with dense clusters of tiny greenish flowers popping up uninvited in your garden, you might be looking at purple amaranth (Amaranthus blitum var. emarginatus). Also known as slender amaranth, this annual forb has a knack for showing up where you least expect it – and while it’s not exactly a garden showstopper, it’s worth understanding what you’re dealing with.
What Exactly Is Purple Amaranth?
Purple amaranth is a non-native annual that originally hails from Europe and Asia but has made itself quite at home across North America. As a forb (that’s garden-speak for a non-woody plant), it lacks any significant woody tissue and completes its entire life cycle in a single growing season. Don’t let the name fool you – the purple refers more to the stems and leaves than any showy purple blooms.
This plant goes by a few different names in scientific circles, including Amaranthus blitum L. ssp. emarginatus and has sometimes been mistakenly called Amaranthus lividus. But regardless of what you call it, the behavior remains the same: it’s a persistent self-seeder that knows how to make itself at home.
Where You’ll Find It Growing
Purple amaranth has established itself across a remarkably wide range, from the Canadian provinces of Nova Scotia, Ontario, and Quebec, down through most of the eastern United States, with outposts as far west as California, Utah, and Washington. You’ll also find it in Hawaii, Puerto Rico, and other Pacific territories.
- Species observed
- No observations
What Does It Look Like?
This isn’t a plant you’d typically choose for its ornamental value. Purple amaranth produces small, inconspicuous greenish flowers arranged in dense, compact clusters. The real identifying features are often the reddish or purplish stems and the tendency for the plant to form somewhat sprawling patches in disturbed soil areas.
Should You Plant It in Your Garden?
Here’s the thing about purple amaranth – most gardeners don’t actually choose to plant it. It’s more likely to choose your garden for itself. While it’s not considered invasive or particularly harmful, it’s also not bringing much to the table in terms of garden beauty or ecological benefits.
The flowers are wind-pollinated rather than insect-pollinated, so they don’t offer much for your local bee and butterfly populations. And aesthetically speaking, there are much more attractive options available if you’re looking for annual color or texture in your landscape.
Growing Conditions and Care
If purple amaranth does show up in your garden (and it probably will at some point), you’ll notice it’s remarkably adaptable. It thrives in full sun and isn’t particularly picky about soil conditions. As an annual, it can handle the climate across most USDA hardiness zones during the growing season.
The care it requires is minimal – perhaps too minimal for most gardeners’ liking, as it tends to self-seed readily and can become weedy if left unchecked.
Better Native Alternatives
Instead of letting purple amaranth take up real estate in your garden, consider these native alternatives that offer similar growing ease but with much more ecological and aesthetic value:
- Native amaranths like Amaranthus retroflexus (redroot amaranth) – where native to your region
- Wild bergamot (Monarda fistulosa) – excellent for pollinators
- Purple coneflower (Echinacea purpurea) – beautiful blooms and great wildlife value
- Black-eyed Susan (Rudbeckia species) – cheerful, long-blooming, and native across much of North America
The Bottom Line
Purple amaranth falls into that category of plants that are perfectly harmless but not particularly helpful either. If it shows up in your garden, you can easily remove it by hand-pulling before it sets seed. While it’s not going to harm your local ecosystem, it’s also not contributing much to it either.
Your garden space is valuable, and there are so many beautiful native plants that can fill the same niche while supporting local wildlife and adding genuine beauty to your landscape. Consider purple amaranth a reminder to be intentional about what you’re growing – and maybe an opportunity to discover some fantastic native alternatives that will make both you and your local pollinators much happier.