Whether you’re a fanatic for foliage-focused plantings or simply appreciate the many ways that colorful leaves can enhance your flowers, it can be hard to resist the latest anything-but-green perennials and woodies in nursery catalogs and garden-center displays. Take one look at the price tags on these beauties, though, and you may be contemplating a loan to bulk up your plant-buying budget. And then, you’ll still have to wait a couple of years for them to settle in and fill out to their full glory.
There’s a way to make your gardening dollars go further and get faster results at the same time: by taking advantage of the many annuals and tender perennials that are easy to grow from seed. They come in a wide range of heights and colors, so you’re sure to find some that can complement just about any bed, border, or container planting you can dream up, and you’ll be waiting only weeks to start enjoying them.
Lovely in their own right, seed-grown foliage annuals are also useful for testing combinations or large-scale planting plans before fully committing to them. If the heights and colors work out, you can then replace them with similar perennials or shrubs; if not, you can easily replace them with another option the following year.
There are so many excellent seed-grown foliage annuals that I’m dividing them up by color. Let’s start the series with the deliciously dark-leaved options.
To add a dark note to the very front of a border, consider ‘Purple Lady’ iresine (Iresine herbstii), also known as beefsteak plant. It grows outward more than upward, generally staying less than around 6 inches tall but spreading several feet by the end of the growing season, swirling around the base of nearby plants, pooling in open spaces to create a beautiful burgundy groundcover, or cascading over the edge of a container. (Available at Seedman.com: Purple Lady)
The effect of ‘Purple Lady’ is like that of a fine-textured, purple-leaved sweet potato vine (Ipomoea batatas)—which, by the way, can itself be started from seed, if you can find a source or collect from your own plants. (Sometimes I find self-sown seedlings of purple-leaved sweet potato the next year, or even years later!)
Dark-leaved lettuces are a super-quick foliage filler you might not have thought of for ornamental plantings. They too are typically in the 6-inch-tall range, at least while in leaf. ‘Merlot’ is my go-to strain for the richest color, but there are other good maroon to bronzy strains with different leaf shapes and textures. (Available at Baker Creek Heirloom Seeds: Merlot Lettuce)
Normally, you’d figure on pulling out the lettuce some time in June, or whenever it starts to bolt (rise in the middle in preparation for going to flower), then replace it with something heat-loving for summer and fall color. One of the neat things about ‘Merlot’, though, is that it looks pretty cool even at the bolting stage.
Strains of mustard (Brassica juncea) with purple to red leaves are another option for quick cool-season color. I particularly like ‘Ruby Streaks’ because of its lacy texture. (Available at Hayefield: Brassica juncea ‘Ruby Streaks’ and High Mowing Seeds: Ruby Streaks Mustard Greens)
Yet another ornamental vegetable for dark, front-of-the-border or container foliage is ‘Bull’s Blood’ beet (Beta vulgaris). It has the advantage of being longer lasting—easily through the summer, at least, or until you pull it out for the edible harvest. (Available at Seed Savers Exchange: Bull’s Blood Beet)
Moving into the slightly taller range…one of my top favorites in the super-dark range is ‘Black Pearl’ pepper (Capsicum annuum). The plants develop their richest leaf color in full sun and not-super-hot weather. If they get a bit of shade, or during the dog days, they may show a bit more green but are still mostly deep purple.
The upright plants generally reach about 18 inches tall, fitting easily into a container or near the front of a border, and branch out some along the upper half to two-thirds, leaving room to plant lower companions close to the base. (Available at Hayefield: Capsicum annuum ‘Black Pearl’ or Botanical Interests: Black Pearl Ornamental Pepper)
Purple-leaved basils (Ocimum basilicum), such as ‘Osmin’ basil and ‘Red Rubin’, have smaller leaves but are very similar in height and growth habit. (Available at Pinetree Garden Seeds: Osmin Basil and Swallowtail Garden Seeds: Red Rubin Basil)
Another especially dark option in this height range is ‘Purple Knight’ alternanthera (Alternanthera dentata). The heavily branched plants usually reach about 2 feet tall and can reach about as wide. Planted in masses, it can make a medium-height, single-season groundcover. In a border, a single plant tends to mingle its stems with nearby companions to create striking combinations. (Available at Kitchen Garden Seeds: Purple Knight Alternanthera)
Generally reaching 2 to 3 feet tall in a pot or in the ground, black-leaved cotton (Gossypium herbaceum ‘Nigrum’) has broader leaves, which give it a bolder texture. (Available at Hayefield but sells out very quickly: Gossypium herbaceum ‘Nigrum’)
The cotton plants are quite upright, so it’s a good idea to plant bushier partners around them. Pairing it with the low Mexican fleabane (Erigeron karvinskianus) wasn’t one of my best ideas, but it did really let the cotton plants stand out.
You’d normally think of celosias (Celosia argentea) for their flowers, but some of them are just as good for foliage. ‘Dragon’s Breath’ is a plumose type usually topping out at 18 to 24 inches, with red-blushed green to distinctly red leaves. (Available at Park Seed: Dragon’s Breath Celosia)
‘Mega Punk’ is a strain of spike celosia (Celosia argentea var. spicata) that popped up here at Hayefield years ago. Generally in the 2- to 3-foot-tall range, its foliage has a purple-red blush. (Available at Hayefield: Celosia argentea var. spicata ‘Mega Punk’)
Seeds also offer some exciting options for dark foliage in grasses. ‘Black Madras’ rice (Oryza sativa) typically reaches about 18 inches tall, in spiky clumps that are narrow at the base and wider at the top. (Available at Hayefield: Oryza sativa ‘Black Madras’)
The odd thing is that the color can read as purple, red, or bronze, depending on the light. The two photos below show ‘Black Madras’ growing in the same place but at different times.
The purple-leaved millets (Pennisetum glaucum) are an excellent choice if you need something taller—in the 3- to 5-foot range. Their leaves are wider than those of most grasses, and with their deep color, they have a very bold, eye-catching appearance. ‘Purple Majesty’ is a good one, but I particularly like ‘Jester’ because it gives different color effects through the growing season: chartreuse at first, then kind of bronzy, and then finally deep purple. (Available at Hayefield: Pennisetum glaucum ‘Jester’)
‘Jester’ also tends to be more compact (shorter by a foot or so) than ‘Purple Majesty’, so it fits more easily into a container.
There are even some shrub-sized annuals that can provide substantial foliage impact in just one growing season. ‘Mahogany Splendor’ hibiscus (Hibiscus acetosella) looks much like a lacy Japanese maple, with deeply lobed, rich burgundy foliage on bushy 3- to 5-foot tall plants. It’s a real beauty! (Available at Select Seeds: Hibiscus ‘Mahogany Splendor’)
‘Hopi Red Dye’ amaranth (Amaranthus) gets even taller: typically 4 to 6 feet, but even higher in really good soil. A single plant makes a strong vertical accent; a group of them creates a bold mass of color.
Though amaranth plants are typically much taller than they are wide, you can keep them lower and wider by snipping out the stem tip when the height is close to what you’d like. (Available at Hayefield: Amaranthus ‘Hopi Red Dye’)
And for foliage color on an annual with serious height and substance, it’s hard to beat ‘Carmencita’ castor bean (Ricinus communis). It never fails to amaze me how a single, bean-sized seed produces a terrifically tropical plant that can easily reach over 6 feet tall and several feet wide in just a few months, even here in decidedly non-tropical Pennsylvania.
Who needs shrubs when you can fill a whole lot of border space with a single packet of castor-bean seeds? (Available at Hayefield: Ricinus communis ‘Carmencita’)
That’s hardly an exhaustive list of purple- to red-leaved annuals you can grow from seed, but it gives you some idea of the many possibilities for single-season foliage plants.
From a combination-planning perspective, near-black to burgundy foliage annuals look fantastic with flowering partners in rich pinks, reds, oranges, and yellows. Or, for a high-contrast effect, consider pairing them with white flowers or silver or bright yellow foliage. All of these dark-leaved beauties are excellent for echoing deep purple to wine-red blooms, as well as dark-leaved perennials and shrubs. And don’t overlook the possibilities of using them to pick up dark centers, speckles, or whiskers in nearby blooms, or the dark stems or leaf markings of more permanent garden partners, adding a subtle but sophisticated touch to your plantings. Have fun exploring your options on the dark side!