Listening to some gardeners talk about it, you would think that a genuinely "perennial" tulip is some kind of holy grail. The dream of a tulip that comes back and multiplies has inspired and then eluded many gardeners. Any skepticism you may have is why I hesitate to make the following claim, but here it is: Wild or species tulips are perennials. Under optimal conditions, they will come back year after year and usually increase in numbers. In many cases, gardeners find themselves pulling out some that have strayed too far.
Species tulips are the wildflowers of the tulip family. The much larger and more extravagant hybrid tulips, bred largely by Dutch horticulturists, are their fancier descendents.
Hardy wild tulips require less work. They are less vulnerable to stormy spring weather, and their generally short stems don't bend in strong winds.
Another appealing feature of species tulips is how they flower. Their flowers usually remain closed through the morning or on cloudy days, showing only the outside color of the petals. When warmed by the sun, they open to reveal another petal color on the inside. It's like having two different flowers in the same space at once. What a treat!
Species tulips propagate quickest given full sun but tolerate partial shade. The only cultural feature they are persnickety about is well-drained soil. Sandy soil is best. If your garden lacks good drainage, work fully composted pine or fir bark or a similar organic amendment into the soil.
The best tulip-planting time depends on where you live. Ideally, wait until the soil temperature is below 60 degrees F. As a general guide, plant in September through early October if you live in USDA Hardiness Zones 4 or 5; October to early November in zones 6 or 7; November to early December in zones 8 and 9; and late December to early January in zone 10 (after refrigerating the bulbs for 8 to 10 weeks).
Set the bulbs in a planting bed or in separate planting holes with their roots or basal plate downward. Plant bulbs 4 to 6 inches below the surface, or three to four times their height. Space the bulbs of most species tulips 2 to 6 inches apart, or three times their width, following the supplier's instructions. Water the bulbs right away to initiate growth. Mulch after planting to help keep soil cool in mild winter areas; mulch after soil freezes in cold-winter areas.
If you live in the South (or mild-winter areas of the West), plant "mild-winter" tulips that thrive in zones 8 through 10: the lady tulip (T. clusiana), the Candia tulip (T. saxatilis), and the Florentine tulip (T. sylvestris). These tulips do not need chilling before planting in these regions. In areas like Tallahassee, Houston, or San Diego, buy these three types of species tulips in the fall, plant them in a cool, shaded location, and forget them. They'll flower in spring and likely for many springs to come.
Most species tulips naturalize-when unaffected by rodents-via seeds, underground stems called stolons, or daughter bulbs. The new plants are usually identical to the parent plant, but beds of seed-grown plants may produce some flower-color variation.
Encourage the bulbs' multiplying tendencies by leaving faded flower heads attached so that seeds can mature and spread. Don't remove leaves until they begin to turn yellow and fall over. Bulb plants use the extra time in leaf to continue photosynthesis and store nutrients for the next year.
Every fall, apply 4 to 5 pounds of the 9-9-6 fertilizer called Holland Bulb Booster per 100 square feet over the tulip bed. If you prefer organic plant food, I recommend Bulb Mate, a 5-10-12 mix of cricket manure, rock phosphate, bonemeal, blood meal, dolomitic limestone, granite meal, and compost. Apply 8 pounds of it per 100 square feet.
Water the growing plants in spring if the garden doesn't receive about 1/2 inch of rain weekly. Species tulips are dormant in the summer and prefer dry soil then, but most kinds adapt to garden situations (the exceptions are noted below).
If you have rodents such as voles or gophers (or what my husband and I call "underground bulb monsters") in your garden, adding a handful of sharp gravel to the hole on the tulip bulb will discourage them from eating it. Don't mulch where rodents are a problem, because they love to nest in mulches. Wire or fabric baskets protect bulbs from rodents, and repellents are available that help deter these pests. Of course, a good cat or two is the best control of all.
You can force species tulips to bloom indoors. In cold-winter climates, pot the bulbs and cover them with about 8 inches of mulch, or store them in an unheated, ventilated basement or garage for about four months beginning in the fall. Move them to a sunny place when shoots appear. In warm climates, store the pots in a cool location, but check for root growth after 8 to 10 weeks, then move them to a warmer location.
Several of these wild tulips have been hard to find in the past, and some still are. All are available via mail-order suppliers, and most garden centers also stock species tulips in the fall.
Most commercially available species tulip bulbs are nursery-propagated and grown, but check with your supplier to be sure they were not collected from the wild.
Native to areas ranging from Europe to central Asia and China, the following 22 species of wild tulips are charming and widely available. All are, technically, "other species." Tulipa fosteriana, T. greigii, and T. kaufmanniana are not commercially available as wild species but are categorized as hybrids with the characteristics of wild tulips.
Bloom season isbased on typical zone-6 bloom times: "early" (March to April), "midseason" mid- to late April, and "late" (April to late May). South of zone 6, blooms come early; north of zone 6, they come later.
Recommended zones are guidelines, not absolutes. Exploit microclimates and provide good growing conditions to promote growth.
T. albertii. Midseason bloom. Height is 10 to 12 inches. Zones 6 through 8.
T. bakeri 'Lilac Wonder'. Blooms early. Height is 6 to 8 inches. Zones 5 through 9.
T. batalinii hybrids. All bloom midseason and grow 4 to 6 inches high. Best varieties are: 'Apricot Jewel'--see photo-its leaves form a lovely rosette; 'Bright Gem'--a fragrant flower of soft sulfur yellow with an orange-sherbet flush; 'Red Gem'--red petals with an apricot glow; and 'Yellow Jewel'--pale yellow flowers with a dusting of rose, and prostrate leaves. Zones 4 through 8.
T. biflora. Blooms early. Fragrant. Height is 4 inches. Each bulb produces one to five small flowers that open wide. Zones 4 through 8.
T. clusiana hybrids. Sometimes called lady tulips, these varieties bloom in midseason on 8- to 10-inch stems. Varieties are: 'Lady Jane'--alternating red petals and white petal-like sepals suggest a candy cane. It is a readily available strong grower; 'Cynthia' (similar to T. clusiana chrysantha)--red petals with chartreuse edges, a purple base, and soft green anthers; 'Tubergen's Gem'. Zones 4 through 10.
T. eichleri (also known as T. undulatifolia). This early bloomer reaches 10 to 12 inches tall and multiplies rapidly. Zones 4 through 8.
T. humilis (also known as T. pulchella). Small, crocus-shaped flowers are normally pale pink with a yellow center, but some are dark purple with black or purple bases. Very early bloomer. One, but sometimes three flowers, to a stem. Height is 4 inches.
Varieties include: T. h. albocaerulea-occulata--white with a deep steel-blue base; 'Eastern Star'--magenta-rose with a bronze-green flame outside and a canary yellow base; 'Lilliput'--red with a violet base and more than one flower per stem; 'Odalisque'--rosy-red outer petals with a silvery glow, striped green at the base, and the inner petals are beet-purple with a large yellow base; 'Persian Pearl'; and 'Violacea'--pointed purplish rose petals with green-tinged lower part and a yellow basal blotch margined with blue or greenish black. Zones 4 through 9.
T. kolpakowskiana. Yellow flowers streaked with red come one to three per stem in mid- to late season on 6- to 8- inch stems. Wavy-edged leaves lie nearly flat against the ground. Zones 5 through 8.
T. linifolia. Blooms midseason on 4- to 6-inch stems. Zones 5 through 8.
T. neustruevae. Blooms early. Height is about 4 inches. Zones 4 through 8.
T. orphanidea. Sometimes called the Spartan tulip, blooms on 8- to 10-inch stems in early spring. Yellow-flowered T. orphanidea 'Flava' is long-blooming. Spreads by stolons. Zones 5 through 9.
T. polychroma. Five blooms per stem appear early in the season. Height is about 4 inches. Zones 5 through 8.
T. praestans. Up to four flowers on 12- to 16-inch stems bloom in midseason. Orange-red 'Fusilier' is shorter but offers up to five flowers per stem. 'Unicum' also has five flowers per stem, but is slightly less cold hardy. 'Zwanenburg' has slightly larger and darker flowers compared to 'Fusilier', but it may be difficult to find. Zones 4 through 9.
T. saxatilis. Also called the Candia tulip, it grows 6 to 8 inches high. In sunlight, flowers open early in the season into an elegant star shape. This species is excellent for mild-winter climates and will multiply rapidly farther south than other tulips. Spreads by fat, white stolons. Zones 5 through 10.
T. sylvestris. Also called the Florentine tulip, the sweet, musk-scented flowers come one or two per 10- to 12-inch stem in late spring. Spreads via stolons. Zones 4 through 9.
T. tarda (also known as T. dasystemon tarda). Fragrant flowers bloom early. Each 3- to 4-inch stem produces up to six flowers. The plant multiplies rapidly. Zones 4 through 8.
T. turkestanica. Up to seven petals bloom on 3- to 10-inch stems. The species is variable, however. Some have black centers, and some have red centers. Blooms early and multiplies readily. Zones 4 through 8.
T. urumiensis. Three to five flowers per stem. Blooms early to midseason. Height is 4 inches. Zones 4 through 8.
T. vvedenskyi 'Tangerine Beauty'. Petals open wide, bending backward in bright sun. Blooms mid- to late season. Height is 8 to 10 inches. Zones 5 through 8.
T. whittallii. One of my favorites and an amazing naturalizer, this tulip blooms in midseason. Height is 8 to 10 inches. Zones 4 through 8.
T. wilsoniana (also known as T. montana). Flowers open wide in full sun, and with the central yellow anthers, the effect is striking. Blooms late. Height is 4 to 6 inches. Zones 5 through 8.