Carol O'Meara, Colorado State University Extension

Carol O’Meara, Colorado State University Extension

BOULDER COUNTY – Looking for a way to celebrate the solar eclipse?  If you subscribe to the Italian folklore that flowers planted during a solar eclipse are more vigorous and vibrant, you could pop a few plants into the ground on August 21. To truly honor the marriage of sun and moon, here are a few suggestions to make your garden the one that eclipses all others.

Day meets night with Evening Primrose, which gets its name from opening large yellow flowers late in the day and closing them the following morning. Easy to grow, this plant is a bit of a sprawler, so give it room to grow that’s away from walkways
or drives.

Choose a well-drained location in full sun for your primrose where it can stay; its deep root system makes transplanting it difficult. A reliable cultivar is Silver Blade (Oenothera macrocarpa subsp. incana), a Plant Select introduction from 1999 that’s hardy to zone 4. Keep an eye out for flea beetles, which can be a pest of this plant.

Containers holding Moon flowers (Datura inoxia) perfume the air with sweet scent. Also called Angel’s Trumpet, the Datura is one of the moon flowers due to its blooming at night with large upward facing trumpet shaped flowers.

Depending on the species and cultivar, flowers may be white, pink, lavender, purple or yellow. Some are double flowered. The plants are usually grown as annuals but can reach two to three feet tall in one season. Place this container in sun; they love warmth and light. All parts of this plant are poisonous.

Another Plant Select introduction, Moon Carrot (Seseli gummiferum), struts its stuff when kissed by lunar light. The silvery-blue foliage is overtopped by umbel flowers that look like clusters of white/pink buttons is unique and interesting in sunlight, but at night it nearly glows.  Planted with darker, more richly hued plants Moon Carrot is a standout performer.

Plant Moon Carrots in full sun and well-drained soil. Since its biennial, the first year the plant forms a non-flowering rosette.  Allow the plant to go to seed to keep your garden in Moon Carrots.

Perennial sunflower (Helianthus maximilianii) is a wildlife favorite with four-inch flowers circling the stalk. It’s perfect to adding color to the back of a bed or in areas where it has room to grow. The plant is allelopathic; this means it can hinder the growth of plants nearby. Plant it in full sun in lightly amended soil.

Prairie Lode Sundrops (Calylophus serrulatus ‘Prairie Lode’) is a sure-fire way to light up the garden from May to September with bright yellow flowers. This Plant Select prairie native is low maintenance, so no need to amend the soil before planting.  Hardy in zones 5 through 9, pop it in the ground soon so that it can get established before the cold sets in and you’ll be rewarded with plenty of flowers next year.

If you have a sunflower or two in the garden and want to harvest its head for fall décor, here’s how:

Sunflowers signal their readiness in several ways: ripe seeds start falling out or the heads droop and the back changes from green to yellow/brown. Petals will be shriveled and falling, leaving the plumped seeds exposed.

At this point – before the seeds start falling – cut the head off the stem, leaving one foot of stem attached. Hang them upside-down in a warm place until dry and the seeds separate easily.

By Carol O’Meara, Colorado State University Extension. Colorado State University Extension, together with Boulder County Parks and Open Space, provides unbiased, research-based information about consumer and family issues, horticulture, natural resources, agriculture and 4-H youth development. For more information contact Extension at the Boulder County Fairgrounds, 9595 Nelson Rd., Box B, Longmont, 303.678.6238, e-mail [email protected] or visit