Cosmos: You Can Grow That!

Cosmos are the annual gifts that keep on giving. And that’s good, because they’re one of the easiest flowers to grow and they come in a huge range of colors, bloom types and varieties.

Cosmos (Cosmos bipinnatus) plants are part of the Aster family, and native to Mexico and some areas of the desert Southwest. Between this classic cosmos and the related sulphur cosmos (C. sulphureus), the flowers can grow in nearly a full range of growing zones – from zone 1 through zone 11.

sulphur cosmos flower orange
Sulphur cosmos in bright orange.

Of course, in nearly all but the hottest of these zones, cosmos grows as an annual and dies back with frost. But if you think that is a good reason to avoid growing the plant, I’d like to convince you otherwise. Cosmos is a prolific re-seeder in even the poorest of garden soils.

cosmos in xeric garden pink
Cosmos that have re-seeded every year for at least five years.

Add Color and Wildlife

Cosmos flowers attract butterflies and hummingbirds, along with other insects. They will bloom from mid-summer through early or mid-fall, depending on your first frost date. You can cut flowers for indoor arrangements, which also can lead to more blooms. I also leave plenty of dying flowers on the stems because they feed finches. I love watching a finch land on the small, swinging branches to peck away at the seeds. In a world in which so many flowers are yellow, it’s so great to enjoy the white, pink and red tones of cosmos in my xeric garden.

Butterfly on bright pink cosmos blossom.
Butterflies and bees love cosmos flowers.

Plant from Seeds

You can plant cosmos from seeds or nursery transplants. I have had mixed luck growing cosmos from seed until this year. I know the flower seeds like loose soils, but with our dry and windy conditions, I found it better to cover the seeds lightly with some compost and water with a soaker hose to prevent washing away.

As for planting again next year, unless you severely disturb the soil where (and near where) you had cosmos last year, you should get plenty of volunteers as soon as summer rains start, and see the seedlings with their fine leaves growing taller as monsoon rains continue. You can help Mother Nature by gently spraying the area where you want the flowers to appear if early-summer rains have been light.

bright pink cosmos flowers
Re-seeded cosmos flowers have maintained their bright colors.

Most cosmos varieties grow tall, maturing at up to four-feet high, so they often work best at the back of a garden.  If you have a bed or meadow filled with cosmos, they tend to support each other and seldom flop over as some plants can when they get tall. Cosmos loves full sun or part shade.

Sit back and enjoy

Once they become seedlings, cosmos do best with nothing but rain water. Overwatering the plants actually can lead to fewer blooms.

red-pink cosmos flower
The tiny needle-like leaves of cosmos and upright growth make the seedlings easy to spot.

There are some areas of the United States that consider cosmos invasive, including a few spots in western New Mexico. And I admit one of the best characteristics of the plant – easy re-seeding – also can mean it pops up where we don’t want it. For example, if I didn’t pull seedlings out of our steps, we would not be able to walk down to the garden. But I leave a few off to the side for compromise. I pull those that block other plants and let the rest grow as they may. They’re crowded, but I love the effect.

cosmos, babys breath, cornflower in small vase
Cosmos as part of some cut flowers adorn my desk on days when I can’t spend much time outside.

You can grow cosmos and enjoy cutting the flowers for indoor arrangements. And have even more fun watching for new flowers to begin popping up the next summer!

you can grow that logo

Favorite Flower: Nigella

I just discovered this delicate, early bloomer in the past few years when friends suggested Love-in-a-Mist (Nigella damascene) seeds from our local iris farm. The foliage looks much like fennel or dill as seedlings sprout, and nigella also is called fennel flower.

pink, purple and white love in a mist flowers
Love in a mist grows from between rocks bordering our xeric garden.

Nigella Is Versatile

We grew multicolored love in a mist in our rock garden. Tim threw the seeds out in fall and by mid-spring, we had fine fern-like leaves popping up from between the rocks. Although Nigella does best in damp sandy soil, ours grew out from under rocks that make up the walls of our xeric garden. The rocks likely held moisture longer than a spot in the open might have. The rocks also trapped the tiny seeds so fewer blew away. Plus, nigella can tolerate dry conditions.

Nigella in rocks at steps in garden.
Here are the same flowers from a wider angle — in the corner to the right of the potted geranium.

But then we tried another approach – we bought a packet of Bridal Veil (Heirloom White Nigella) seeds from Renee’s Garden and sowed them in early summer in a blank spot of our vegetable garden. This soil is far better in quality, and the seeds received consistent drip watering. The flowers were taller and stunningly white, with maroon to black centers. The plants reproduce from seeds, assuming some seedheads are left on plants at the end of the season.

bridal veil white Nigella.
These heirloom bridal veil flowers thrived in our vegetable garden and the contrast of colors is gorgeous and fun.

Sow in Fall or Spring

Although most instructions for growing nigella say to sow in spring, you can sow them in fall in areas with mild winters. They need full sun and grow in zones 2 through 10. That worked well for us last year, but this winter has been dry and consistently colder, so I’m anxious to see how many reseeded in our gardens. The bridal veil flowers in our vegetable garden bloomed later in the year, but were planted later. Sowing the seeds a few weeks apart in spring and fall can help ensure constant blooming of nigella in summer.

overhead view of love in a mist
The many colors of love in a mist add interest to the garden or flower arrangements.

Use as a Cut Flower

You can cut nigella blooms for flower arrangements, and even better, cut some of the seedheads. If you cut the flowers to enjoy indoors, leave a few blossoms on the plant so they can dry and drop seeds for the next year. If you get too many, thin them out while small. Enjoy the seedheads after flowering by cutting their stems just after flowers fade, and hang them upside down away from direct sun.

nigella seedpod and flower
Nigella seedhead after blooming alongside remaining white flower.

Nigella is easy to grow and a great addition to any xeric garden!

nigella seedpod
A nigella seedpod. I can’t wait to try drying some of these this summer.

 

 

 

 

 

Mix Up Your Garden Palette

Our low-water garden has lots of yellow. Maybe that’s true everywhere. And it’s a bright, happy color. But we like a little more variety, and it’s easy to add pops of color a little at a time, or with annual plants. Here are a few tips for finding plants of many colors.

yellow blooms
Yellow flowers like the ones on this chocolate flower plant (Berlandiera lyrata) are gorgeous, but I like to mix it up.
color mix in garden
When the butterfly bush blooms, we’ll have deep purple, red, and yellow. I’m adding a few low annuals to the front corner, which is closest to the patio.

Find flowers by color

Although you’re used to a favorite flower blooming in a particular color, there likely are hybrids with colors you hadn’t considered. For example, we think of sunflowers as bright yellow, but I love the cinnamon varieties. I’ve got some seeds in again, in the hopes that bugs and deer leave them alone.

larkspur pink lilac
Larkspur grow wild in our garden, and although most are a deep violet, we also have lilac, white and pink flowers.

One way to find flowers in complementary colors is by using apps and online databases. For example, the LadyBird Johnson Wildflowercenter’s database includes bloom color, along with native states and sun and moisture requirements in its combination search. For a simpler search, try a list like the one maintained by ProFlowers, which lists flowers by color next to illustrations and a brief description. Just beware that national lists of flowers often include varieties that do poorly in some zones or soils or need more water than those in a xeric garden. Be sure to read the descriptions or do a little research before making your final decision. You can also try apps that either have pictures shared by posters or plant identification. If you can find a local or regional app, even better.

White and red roses offer pretty contrast at the Hondo Iris Farm. If the plant isn't marked, just ask.
White and red roses offer pretty contrast at the Hondo Iris Farm. If the plant isn’t marked, just ask.

Wander around a nursery

If you feel a national list might isn’t giving you enough choices for your area, visit a locally owned nursery. Although they’ll carry some annual varieties that aren’t perfect for the community’s climate, they also carry plenty of knowledge and tend to feature plants that are native or adapted to local growing. If you do find a few annuals either at a local or chain nursery, limiting the number to a few pots or a corner of a bed uses less water, time and money than basing your garden color plan on annuals. Most nurseries separate perennials and annuals to help shoppers.

plants from local nursery
Bringing home the plants from our local nursery. I got a few annuals to add more red, white and black to our garden. And sometimes, the foliage adds lots of color, like with my new barberry.

Make notes as you pass homes and businesses

If you’re walking to a restaurant in town one night and spot a flower with a color you love or know would add variety to your garden, take a photo of the plant and a close-up of the flower. This will help you compare what you saw (and photos work much better than memory) with identification apps, databases and local gardening books. Including the entire plant in the photo helps you remember the type of foliage, height and spread of the flowering ornamental.

Flax and pine leaf penstemon color complement one another. A photo of the penstemon's leaves helps identify it.
Flax and pine leaf penstemon bloom colors complement one another. A photo of the penstemon’s leaves helps identify it.

Color really is a matter of personal choice, and with the recent National Pollinator Week in mind, I try to choose a few new plants for their ability to attract bees, butterflies or birds. For example, studies have shown that bees gather more nectar from purple or violet flowers than from any other color.

Bees love the purple flowers on the herb sage.
Bees love the purple flowers on the herb sage.

Keep it simple and choose what you like, but remember not all plants bloom at the same time, so your color variety might be seasonal or in stages. That’s great too though, so you and the pollinators can enjoy some new blooms every few weeks.

Bees really go nuts in cactus blooms.
It looks like the bee on the upper right dove head-first into this prickly pear bloom.