Chrysogonum virginianum goes by several common names, including golden star and green-and-gold, referring to its combination of attractive green foliage and upward-facing star-shape yellow blooms. This low-maintenance native perennial plant forms a spreading mat in sun or shade but does not spread aggressively. Here’s what you need to know to grow Chrysogonum virginianum in your own garden.
I. Appearance and Characteristics
Chrysogonum virginianum, the golden-knee, green and gold, or goldenstar, is a North American species of plants in the family Asteraceae. It is native to the eastern United States from New York State and Rhode Island south to Louisiana and the Florida Panhandle.
The species is sometimes grown as a perennial ornamental because of its showy flowers. It is usually propagated by root cuttings.
Green and gold (Chrysogonum virginianum) is a low-growing perennial that will grow from 30 to 61 cm tall and spreads to 46 cm wide. Commonly found growing in woodland areas of eastern North America. Makes a great ground cover in shady areas. Prefers partial to full shade. Blooms spring and summer with golden yellow, star-shaped flowers.
II. Chrysogonum Virginiaum Varieties
- Chrysogonum virginianum var. australe
Commonly found in Florida, Georgia, Alabama, Mississippi and Louisiana, this variety is an ideal option for those looking for low maintenance plants. They bear yellow disk flowers as flowering stems rise from leaf axils in early spring with a low-growing mat of dark green leaves.
This variety is commonly referred to as green and gold. What makes var. australe different from the other varieties of the green and gold plant are its shorter flower stem and more rapid expansion of roots.
- Chrysogonum virginianum var. brevistolon
Also known as golden star plant, Chrysogonum virginianum var. brevistolon of the green and gold groundcover is a low-growing perennial. It is ideal for woodland path and rock gardens. You can pair them up with Virginia bluebells and have a beautiful looking garden!
It has bright green foliage and showy yellow disk flowers having a star-shaped structure. Their appearance resembles a daisy and has five rounded yellow petals. This variety can bloom from spring to fall in cooler climates.
However, if you live in warmer areas, the blooming may stop on hot summer days. Chrysogonum virginianum var. brevistolon is common in Georgia, Alabama, Carolinas, Tennessee, and Kentucky.
- Chrysogonum virginianum var. virginianum
This cultivar of Chrysogonum virginianum is the most common variety that you’ll find. They produce daisy-like yellow flowers from March to October. May is the peak bloom time. The foliage is dark green and can grow up to nine inches in height. Chrysogonum virginianum var. virginianum is able to retain its evergreen leaves throughout the year and make an ideal choice for a rock garden with its low-growing best ground cover appearance.
III. How to Grow and Care
Sunlight and Temperature
Chrysogonum virginianum plants grow well in locations with part shade to full shade, or areas of sun dappled part shade. They can tolerate full sun, but you have to make sure the soil remains consistently moist. The ideal location is a partly shady sun-dappled area.
Extreme weather, and hot summer climates of Florida and Louisiana may cause the plant to brown. Give it plenty of shade if you live in a region with hot summers. In cold it will die back, but it should return in spring. Since it’s semi-evergreen, don’t worry about the plant browning in winter. This is a natural part of growing green and gold in colder regions.
Watering and Humidity
Chrysogonum virginianum plants prefer medium to wet soil. If you decide to plant green and gold in a location that is windy or gets more sun rather than part shade, you need to water the soil frequently or else it will dry up and your plants will suffer. Make sure to increase watering frequency during the heat of summer as well.
As long as you follow these watering guidelines for these native plants, you’ll acheive the moderate humidity needed to care for this plant.
Soil
Golden knee plant prefers neutral or acidic soil with pH value less than 6.8. Although it can handle wet soil that occurs along woodland paths, allow for some drainage or the plants’ roots will suffer root rot. Organically rich soils and consistently moist soils are best. Provide your planting area with amendments of rich potting soil or well-rotted compost to retain moisture and keep your plants happy.
You can add composted pine bark at 20% volume into heavy clay soils to avoid the possibility of roots rotting. In this same vein, well drained soils are a must!
Fertilizing
Although this yellow-flowered ground cover doesn’t absolutely need fertilizer, you can feed it with a slow-release, organic fertilizer if you choose. Mix into the top 1″ of soil before planting, or amend by sprinkling in spring. Don’t overdo it, though, as many native plants can suffer from too much assistance in the form of fertilizer.
Planting Instructions
Plant in the spring in prepared soil, adding organic matter if needed. Place nursery-grown plants in a hole the size of the root ball, spacing the plants 12 to 18 inches apart. Water them well, and mulch them to retain moisture while the plants become established. After the plants spread and fill in, they can be divided every other year in late spring.
Pruning
As flowering stems rise from leaf axils of your foliage mat in spring, your C. virginiaum plants will produce their bright yellow flowers. You can snip these flower stems as the flowers fade in fall to prevent self-seeding. Feel free to prune the green parts of the plant at any time to provide air circulation and shape the plant.
Propagation
The easiest way to increase your stand of golden star is to divide the plants in late spring. Dig up large clumps and divide them into sections. If the center appears overcrowded, discard it and replant the vigorous outer sections. If stolons (creeping horizontal runners) develop new plants at their tips, remove the rooted plantlets and replant them wherever you want a low-growing groundcover. You may find seedlings near the base of the mother plant that can be dug and replanted.
Repotting
Although most gardeners opt to grow as a ground cover, you can easily cultivate in a container garden as well. To repot, simply divide it by its rhizomatic roots, looking for separations between growth points, and move the divisions to another pot. Pretty soon you’ll have another full container or growth!
Pests and Diseases
- Common Pests
They rarely experience pest problems. However, snails and slugs can eat holes in newer spring foliage. It won’t cause any serious long-term damage, though. You can eliminate them by using iron phosphate, the beer trap, or a variety of other slug and snail control methods.
- Common Diseases
Every so often your golden star, with its star-shaped flowers, may run into powdery or downy mildew issues. Both present as fungal growth on leaves. Downy mildew growths are on both the leaf surface and undersides. Powdery mildew grows solely on the tops of leaves and flower stems.
For care for those particular diseases, remove affected leaves and flower stems from the foliage mat as they crop up. Try to consistently prune to promote good air circulation, and keep other plants away from affected ones.
III. Uses and Benefits
Chrysogonum is a perfect choice as a groundcover for woodland gardens, naturalized areas, or beneath trees and shrubs. It’s also useful for edging pathways or adding to borders and rock gardens. Considered semi-evergreen, this plant retains most of its leaves except in the coldest parts of its range.
