Several groups include tulips that have been in commercial production since the beginning of the 18 thcentury.
Group 1: Single Early
Single early tulips flower in mid-spring with relatively large, round flowers, neat foliage and short, sturdy stems no more than 16 inches tall. This stature makes them ideal for containers. Many cultivars still in production date back to the mid-19thcentury along with a few that first appeared in the early 18th.
Group 2: Double Early
These double-flowered tulips are shorter, bloom a little later and hold their flowers longer than their single counterparts. The long-lasting blossoms have so many petals that they resemble peonies!
Group 3: Triumph
Robust, mid-season tulips created by crossing early and late varieties, Triumphs form a widely varied group that offers everything from compact, rounded flowers to those with long, slightly flared petals. These flowers bloom on strong, upright stems standing 16-20 inches high.
Group 4: Darwin Hybrid
These mid-season giants are a 20thcentury innovation created by a brilliant breeder (Dirk Lefeber) who crossed 19thcentury Darwins with Tulipa Fosteriana. Known for their giant, pyramid-shaped buds and their height. Darwin Hybrids are best massed in beds or as long-lasting cut flowers. Certain varieties will perennialize if their foliage is allowed to die back naturally
Group 5: Single Late
Regal and tall, Single Late Tulips bear relatively delicate, orbed flowers on stems of 24 inches or more. Created in the 20thCentury through a series of hybrid crosses that led to a wide range of vivid hues, the elegant flowers win admirers everywhere they are planted.
Group 6: Lily-flowered
Lily flowered tulips bloom mid to late in the tulip season, and while they come in fewer colors than other groups, their delicate, curved petals are often trimmed in contrasting colors. These slender, beautifully flared tulips rise on narrow stems that bend and sway gracefully with even the slightest breeze.
Group 7: Fringed
Fringed Tulips arose from mutations within other groups and as a result, bloom at varied times, rising on stems that range from short to tall. With petals that may be delicately crimped, wildly cut, or even almost feathery, they bring a startling beauty to gardens wherever they are planted.
Group 8: Viridiflora
Tulips in this group open late in the season with green buds that gradually reveal their base color while retaining a vivid green steak from base to tip. The form of these flowers is varied enough to include single, double, parrot and lily shaped blossoms on stems that range from 12 to 20 inches.
Group 9: Rembrandt
Though Rembrandt is not known for his tulip paintings, he was the leading painter of the Dutch Golden Age and flamed and feathered tulips that resemble the famous broken tulips of that era are collectively referred to as Rembrandts. Large commercial growers no longer offer true broken tulips, so those now sold as “Rembrandts,” despite the flaming and feathering of their satin petals, are stable mutants of healthy plants from many of other groups. Thus they come in a variety of shapes and sizes and bloom from early spring until late in the tulip season.
Group 10: Parrot
Parrot tulips are as flamboyant as their name suggests, with elaborately cut, curled and ruffled single petals in a wide range of colors and patterns. These gorgeous flowers mutated from Triumph tulips and bloom late on stems from 16 to 24 inches tall.
Group 11: Double Late
Showy flowers, double late tulips are rounder than their earlier cousins and usually much taller. They flower in May in a wide range of colors and patterns.
Group 12: Kaufmanniana
Petite and very early flowering, Kaufmanninnas are often distinguished by beautifully mottled foliage with bi-colored flowers that open flat close to the ground. They are often called ‘water lily tulips’ for their resemblance to the aquatic flowers that are no relation at all.
Group 13: Fosteriana
Popularly known as Emperor tulips, these broad-leafed plants stand from 10 to 16 inches high with unusually large flowers. Like Kaufmanninnas, they flower early in striking single colors.
Group 14: Greigii
Another petite tulip, Greigiis feature distinctive mottled or striped foliage that spreads close to the earth. The relatively large flowers on short, sturdy stems flower early, but a bit later than Kaufmanninnas or Fosterianas.
Group 15: Miscellaneous
As the name suggests, this category covers a wide range of varieties and cultivars with that don’t quite fit any other grouping. For the most part, these are low growing, small-flowered tulips with a delicate charm, though occasionally members of the group will raise their petals high. They flower from early to late in the season, depending on the specific variety.