Tulip

About Tulip

Tulips are fall-planted bulbs that bloom in mid to late spring in almost every color except true blue. Big hybrid tulips usually bloom well for only a few years, so many gardeners treat them as annuals, while small species tulips come back more reliably. Deer and rabbits browse them, squirrels dig up new bulbs, and mice and voles eat the bulbs.

NC State lists zones 3-8; tulips need 12-16 weeks of winter cold, so in the warm South chill the bulbs in the fridge (away from fruit) until planting and expect one season of bloom (Clemson).

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Plant bulbs in fall once the soil has cooled below about 60 F: mid-September to mid-October in Minnesota, October in Iowa, and late December or early January in coastal South Carolina (UMN, Iowa State, Clemson). Get them in early enough to root before the ground freezes (South Dakota State says 4-6 weeks before), and set them 6-8 inches deep, pointed end up.

Soil

Well-drained soil rich in organic matter; bulbs rot in wet ground, and species tulips handle heavy clay better than big hybrids (NC State, Iowa State, Wisconsin Extension).

Loosen well-drained soil about a foot deep and mix in 2-3 inches of compost; aim for pH 6-7 (Clemson, Penn State). If a soil test calls for it, Iowa State works in 2-3 lb of 5-10-5 or 3-4 lb of bone meal per 100 sq ft.

Feeding

• Early spring, when shoots come up (bulbs you plan to keep for years): balanced fertilizer such as 10-10-10. Clemson suggests 1-2 lb per 100 sq ft, given each fall and again as shoots appear; Illinois uses about 5 Tbsp per 10 sq ft. Follow a soil test and water it in.
• Right after the flowers fade: fertilizer such as 5-10-5. Iowa State applies 2-3 lb per 100 sq ft after bloom while the leaves are still green; Rutgers and Illinois advise against feeding once flowering has started, so keep it light.

Don't cut, braid or tie up leaves until they turn brown, and don't bother feeding after the leaves die back, since the bulb can't use it then (Iowa State, Colorado State). Extra nitrogen and wet leaves encourage botrytis blight (Utah State).

Harvest

Tulips bloom from early April to late May, depending on the type (Iowa State). Snap off faded flowers so the plant doesn't make seed, but leave the leaves until they turn yellow-brown, about six weeks (Clemson). They make good cut flowers (NC State).

Varieties (23)

Pests to watch for

Aphids, Slugs, Brown garden snail, Deer, Rabbits, Tree squirrels, Voles, Eriophyid mites (rust, bud, blister and gall mites), Chipmunks, Narcissus bulb fly

Diseases and problems

Gray mold (Botrytis), Mosaic viruses, Bulb rot

In the kitchen

NC State says tulip petals are edible, with a mild taste like lettuce, peas or cucumber. The bulbs are toxic; people ate them only in wartime famine.

Safety: All parts can upset the stomach if eaten, and the bulbs have the most toxin. Handling bulbs can cause an itchy, tingling skin rash in some people, so wear gloves (NC State).

Pets: Toxic to dogs, cats and horses (ASPCA): tulipalin can cause vomiting, drooling, diarrhea and depression, and the bulb is the most toxic part.