How to Plant and Grow Crossandra

A long-lasting, colorful plant, crossandra can bloom almost nonstop all year long in the right conditions. With its bright orange, yellow, salmon, and pink flowers, it's grown as a perennial in warmer Zones 10-11 or an annual in others. Crossandras also work as houseplants with their glossy, deep green foliage that looks good even if they aren't in bloom.

Unlike many common flowers, the blooms of crossandra are asymmetrical and relatively one-sided. Also, all of the reproductive parts are hidden in the tube of the bloom, so they require specific pollinators to create their seeds. The five-petaled flowers are borne on columnar square bloom stalks, which are unique.

Butterflies are very fond of crossandra and can be found visiting them for their delicious nectar.

Where to Plant Crossandra

While crossandra is known as a florist plant in northern climates, it can make a great bedding plant in the South. The deep emerald green glossy foliage creates a foil for other plants to play against, and the brightly colored orange blooms add color all season long.

Crossandra can tolerate high heat and sun but does best with partial shade during the hottest time of the day or with dappled shade. Crossandra thrives in humidity; its leaves should be regularly misted if grown indoors.

How and When to Plant Crossandra

Plant crossandra in the spring in moist, well-draining soil. It will grow quickly in the right conditions.

Crossandra Care Tips

Despite their delicate appearance, crossandras are pretty tough plants. With basic care and a little attention, they'll thrive and grow.

Light

Crossandra does best in indirect sunlight that's bright and warm. A shade garden is an ideal location for them when planted outdoors. Indoors, place them near a sunny window.

Soil and Water

Don't mistake crossandra's drought tolerance for heat tolerance. Crossandras need supplemental water during dry weather, especially during the sweltering days of the summer. Keep soil moist and water every other day during the growing season. Never water with cold water, which can cause root shock and lead crossandras to die.

Plant them in well-drained soil, preferably with a decent amount of organic matter. They prefer slightly acidic soil with a pH of 5.8 to 6.5. If the pH is off, condition it, so it's hospitable for crossandras. In drier soils, adding compost and even peat moss would help retain water in the soil.

Temperature and Humidity

Outside of their long bloom time and glossy foliage, one of the most appealing things about crossandras is their impressive tolerance to heat. They have no problem making it through even the hottest summer heat in the south. They won't tolerate cold, though. Anything below 55ºF will cause leaf damage.

Keep crossandra comfortable with plenty of humidity. Mist leaves indoors and out if needed, and for indoor plants, keep pots on top of trays of pebbles and water to give them the moisture they need.

Fertilizer

Outdoors, crossandra should be fertilized monthly in summer and every two months or so during the winter months using a granular nutrient. Err on the side of caution when fertilizing since over-fertilization can be damaging. Indoors, use a liquid fertilizer at half-strength every two weeks during the summer and every month during winter.

Pruning

Crossandra can have a loose plant habit and may need some pruning and pinching to encourage good branching and an overall bushier plant. Planting in more sun will also achieve this, as shadier-grown plants will be sparser and loosely branched. It's best to start with good branching at the base, so pinch plants early to encourage branching.

Potting and Repotting Crossandra

Avoid repotting crossandras if you can since they don't react well to being transplanted. It's unnecessary to repot crossandra more than every few years, even if they're rootbound. When you need to repot, use a terra-cotta planter with plenty of drainage. Add pebbles to the bottom of the pot, which should be 2 inches larger than the existing pot. Make sure the plant is moist before moving, and water it well after repotting and filling with soil.

Pests and Problems

Treat infestations of common pests like aphids and mites as soon as you see evidence of them, including white powder or small webs. Try using a blast of water to start, and if that doesn't work, use a spray with 70% isopropyl alcohol. Avoid chemical treatments if possible.

How to Propagate Crossandra

Crossandra can be propagated from stem cuttings. Cut stems from existing plants and dip in root hormone. Add to a pot with a seed-starter mix. Keep the pot with cuttings on a warming mat and regularly mist the soil until you see new growth. Once new growth emerges, move it to your desired location if the temperature is warm enough. Otherwise, keep it indoors until then. If you're growing your propagated stems indoors, you'll need to repot after a month or so to allow for rapid growth.

Types of Crossandra

Crossandra can also be found in quite a few warm colors, but orange is the most prevalent.

Orange Marmalade Crossandra

Crossandra infundibuliformis 'Orange Marmalade' is a beautiful orange variety with great garden performance. Zones 10-11

Crossandra Companion Plants

French Marigold

French marigolds tend to be frilly, and some boast a distinctive "crested eye." They grow roughly 8-12 inches high with a neat growth habit and elegant dark green foliage. They do best in full sun with moist, well-drained soil, will flower all summer long, and may reseed. Zones 2-11

Pentas

Pentas is one of the best butterfly and hummingbird-attracting plants around. It blooms all summer long, even during the hottest weather. The plant grows well in containers and the ground—and makes a good houseplant if you have enough light. It does best in full sun and moist, well-drained soil. Pentas is grown as an annual in most parts of the country, but it's hardy in Zones 10-11. Plant it outdoors after all danger of frost has passed.

Zinnia

A packet of zinnia seeds will fill an area with gorgeous flowers in a few weeks in a fantastic array of shapes and colors. Zinnias are so highly attractive to butterflies that you can count on having them in your garden every afternoon. Zinnias grow quickly from seed sown right in the ground and do best in full sun with dry to well-drained soil. Zones 2-11