Despite its common name, creeping zinnia (Sanvitalia procumbens) belongs to a different plant genus than the true zinnias (Zinnia spp.). It gets its name because the oval, pointed leaves bear a strong resemblance to those of the zinnias. And it is like zinnia in another way: It has a very long bloom period with colorful flowers that have the same daisy-like shape common to all members of the Asteraceae family. Creeping zinnia is a cheery annual plant with a spreading nature and low, 6-inch stature, ideal as groundcover or for planting in containers as trailers. The fine green foliage is unique in itself, but the small yellow blooms steal the show and have been compared in appearance to sunflowers, albeit a miniature version. Creeping zinnia is a true annual that dies at the end of the growing season, but its abundant blooms and carefree nature make it worth re-planting year after year.
Creeping zinnia is normally planted from potted nursery starts in the spring after the threat of frost has passed, though it is also easy to grow from seed. Like most true annuals, it is a fast-growing plant that will flower in its first season—about 10 weeks after seeds are planted.
|Common Name||Creeping zinnia, Mexican creeping zinnia|
|Botanical Name||Sanvitalia procumbens|
|Plant Type||Herbaceous annual|
|Mature Size||4–6 in. tall, 12–18 in. wide|
|Sun Exposure||Full to part sun|
|Soil pH||Acidic to slightly alkaline (5.5–7.5)|
|Flower Color||Yellow, orange|
|Hardiness Zones||2–11 (true annual, grown in all USDA zones)|
|Native Area||Central America (Mexico, Guatemala)|
Creeping Zinnia Care
Creeping zinnia is an exceedingly easy plant to grow in a full-sun or partial shade location in moderately fertile soil, provided it gets sufficient water. It thrives in summer conditions and won't shrivel up even in the face of high temperatures and humidity. Creeping zinnia requires regular watering but does not tolerate soggy conditions.
Creeping zinnia is often planted in spring from potted nursery plants after the soil has fully warmed in the spring and nighttime temperatures are reliably above 50 degrees Fahrenheit. Loosen the soil thoroughly, adding organic amendments such as peat moss or compost, if necessary. Plant so the top of the root ball is at the soil level.
Many people, however, prefer to direct sow seeds in the precise locations where they want plants to grow, since creeping zinnias may react badly to transplanting. Direct-sown seeds are usually planted as soon as the ground can be worked in the spring.
Creeping zinnia will grow well in full sun or partial shade conditions, but its true flowering potential depends on direct sun for six to eight hours per day. In spots that receive just four to six hours of sun, these plants will generally fare fine but won’t have the same abundant blooms
These plants can tolerate a range of soil types, including average to relatively fertile, humus-rich conditions. However, creeping zinnia requires that soil drains well. Otherwise, its roots can become waterlogged and rot.
While creeping zinnia enjoys hot weather and tolerates periods of drought, don’t let this fool you into thinking that this plant won’t need regular watering. It’s important to keep the plant from becoming waterlogged, but it prefers consistently medium-moist soil conditions. For this reason, you might need to water these plants once or twice daily if grown in a container during stretches of dry weather. Aim for moist but well-aerated soil that dries out slightly between waterings, but don't allow the soil to become overly dry and crumbly.
Temperature and Humidity
Hot temperatures and high humidity will make creeping zinnia feel right at home. Native to Central American countries Mexico and Guatemala, these plants thrive when the temperature rises and won’t wilt in a hot climate. But they’re only moderately tolerant of cool weather and will fade and die once the average nightly temperature dips below 50 degrees Fahrenheit.
For a healthy, abundantly-blooming plant, provide at least moderately fertile soil conditions. Creeping zinnia doesn’t have overly specific or substantial nutritional needs, but if the soil you plant it in is less than average, you might need to use organic or a balanced conventional fertilizer.
Creeping zinnia planted in containers or pots often benefits from a slow-release fertilizer or a periodic application of liquid fertilizer to support the overall growth and health of the plant.
Types of Creeping Zinnia
There are more than a dozen named cultivars of creeping zinnia, mostly bred to exhibit small variations in flower shape and color or differences in foliage. Consider these recommendations:
- ‘Sprite’ series features semi-double flowers in shades of orange and yellow with dark brown centers. Plants are 10 to 12 inches tall.
- ‘Gold Braid’ is a profuse bloomer with golden-yellow flowers with dark brown centers.
- ‘Irish Eyes’ has orange-yellow flowers with green centers. Plants are a compact 6 inches in height.
- ‘Mandarin Orange’ features double flowers that are a deep, rich orange with dark brown center disks, closely resembling miniature sunflowers.
Deadhead the spent flowers regularly to keep the plants looking neat and to promote continued blooming. Stems that become too long can be clipped back to keep the plants nicely compact.
Propagating Creeping Zinnia
Creeping zinnia can be propagated in several ways: from seeds collected from the flower heads; by dividing the rootball into separate sections for replanting; or by taking stem clipping to root in a growing medium. In commercial settings, it is normally propagated by seed, since the plant is not fond of being transplanted. But home gardeners often use the stem-cutting method to propagate new plants indoors over the winter, thereby keeping favorite plants alive. Here's how to do it:
- As the weather begins to cool in fall, use sharp pruners to clip 6- to 8-inch stem cuttings from healthy, actively growing plants. Remove any flowers and flower buds, and also remove the leaves from the bottom 2 inches of each cutting.
- Dip the cut end in rooting hormone, then plant the cutting in a 4-inch pot filled with a seed-starter mix or standard potting soil.
- Place the pot inside a loosely secured clear plastic bag, and set it in a location with bright, indirect light. Inspect the pot every few days and water lightly if the potting medium begins to dry out.
- Check for root development every week or so by tugging gently on the stem. When you begin to feel resistance, it means the cutting has developed roots.
- When an ample network of roots has developed, remove the pot from the plastic covering and continue to grow it in a warm, sunny location. The plant can continue to grow indoors until spring. Plant it outdoors once nighttime temperatures are reliably above 50 degrees Fahrenheit.
How to Grow Creeping Zinnia From Seed
Starting creeping zinnia from seed isn't very complicated, but be aware these plants don't always tolerate being transplanted. For best results, consider direct-sowing seeds in the location where you want to grow them rather than in starter trays. The seeds are relatively easy to collect from individual spent blooms, though the small size of the flower heads might make it somewhat tedious work. They store well over the winter and can be planted in the spring.
These seeds require sunlight to germinate, so don't bury them under a layer of soil. Instead, lightly press them into the soil surface or loosely cover them with peat moss. Water them daily and keep the soil moist for the seeds to germinate. It's always best to read the recommendations on the seed packet for specific sowing and care instructions.
Plants will bloom about 10 weeks after the seeds are sown. Many gardeners seeking the earliest possible garden bloom like to start them indoors about two to three weeks before the expected last frost date.
Potting and Repotting Creeping Zinnia
The low growing habit and abundant blooms of creeping zinnia make it a great option for container culture. These plants will fill the container, window box, or another planter with small, beautiful blooms all summer long. Keep in mind that to grow these plants successfully in containers, you'll need to ensure that they have adequate drainage. Use a quality loose and lightweight potting mix to ensure the roots don't become saturated with too much water.
Container-grown plants typically need more feeding than garden plants, mostly because the frequent watering quickly leaches nutrients from the potting medium. You might find it necessary to provide supplemental fertilizer for creeping zinnias grown in containers. Time-released or granular fertilizer pellets or a balanced liquid formula will generally give these plants a needed boost if they are not blooming as heavily as you want.
These frost-tender plants are normally just pulled up and discarded at the end of the growing season. If left in place, though, birds will arrive to pluck at the dried flowers for their edible seeds.
Common Pests & Plant Diseases
These sturdy little plants have no notable pests and diseases to worry about. But like almost any garden plant, creeping zinnia may occasionally be troubled by minor fungal leaf spots or powdery mildew. You can minimize these problems with careful watering by ground-level soaking rather than overhead spraying.
How to Get Creeping Zinnia to Bloom
The general prescription for good blooms with creeping zinnia is to make sure they have plenty of water and sun—that's usually all it takes. In most situations, these plants will bloom vigorously all summer long—right up until cool fall weather sets in. In addition:
- Regular deadheading of spent flowers will prompt continued blooms.
- Long, leggy stems can be cut back to force denser growth and more flowers.
- Container-grown creeping zinnias may benefit from extra feeding. However, with garden plants already growing in suitably fertile soil, too much fertilizer tends to make for long leggy stems that don't produce as many flowers.
Common Problems With Creeping Zinnia
Although they are largely trouble-free, creeping zinnias may cause gardeners concern about these symptoms:
Seedlings Die Immediately After Planting
Even with potted nursery starts, transplanting creeping zinnias should be done very carefully so as to avoid disturbance of the roots. These plants often resent being moved, so treat them with kid gloves to make sure they survive transplanting into the garden. Some gardeners prefer to direct-sow the seeds in the exact locations where they want the plants to grow to avoid this problem.
Plants Have Become Sparse
When growing in fertile soil or when given a lot of fertilizer, creeping zinnias can develop long, leggy stems that are somewhat bare except at the tips. These leggy stems can be aggressively cut back to near the base of the plant, which will stimulate new growth and cause the plant to become fuller and bushier.
How should I use creeping zinnia in the landscape?
Creeping zinnias are often used as foreground bedding or edging plants in sunny border gardens, or in sunny rock gardens. Planted over large open sunny areas, they can make a colorful seasonal ground cover. They are also a very dependable plant for window boxes, hanging baskets, and large mixed patio/deck container gardens.
Do creeping zinnias self-seed in the garden?
Yes, if the flower heads are left on the plant, the tiny seeds often fall into the soil and take root. But these volunteers are not easy to dig up and move, so it's best to leave them in place to colonize. A small patch of creeping zinnias can be self-sustaining from year to year if you live some flower heads in place to drop seed and produce volunteers the following spring.
Are there any standard zinnias that have this creeping, trailing habit?
Most standard zinnias are upright plants, though some are quite short. But for a trailing habit similar to that of the creeping zinnia, try one of the cultivars of Zinnia augustifolea (spreading zinnia). They will have a similar growth habit to creeping zinnia, but they offer a considerably wider range of flower colors.