When to Plant Tulip Bulbs: Fall Planting Dates Where You Live

Plant tulip bulbs in fall, once nights have cooled into the 40s°F and before the ground freezes. In most of the northern US that means late September to mid-October; in the Mid-Atlantic, the lower Midwest and the Pacific Northwest, October into November. Where winters stay mild, as in Texas, Florida, the Gulf Coast and coastal South Carolina, chill the bulbs in the refrigerator first and plant them from mid-December to early January.

We turned that advice into dates. Using NOAA’s 1991–2020 climate normals, we found when typical night lows fall from 50°F to 40°F in 24 cities, then checked those dates against 16 planting calendars published by extension services.¹ The median first frost fell inside 11 of the 12 fall calendars. We also counted cold winter days by hardiness zone. In zone 8b, only about 1 in 6 sampled ZIP codes gets the 13 cool weeks tulips need, yet Seattle, in zone 9a, gets 19.

Tulip planting dates for 24 US cities

South Dakota State University Extension gives a planting cue that works almost anywhere in the North. Start planting:

if the nighttime temperatures stay in that 40 to 50-degrees Fahrenheit range

SDSU adds that bulbs should be in the ground four to six weeks before the soil freezes.³ NOAA normals include the average daily low for every month, so we can date the first half of that rule: the day the normal nightly low drops to 50°F, and the day it reaches 40°F, at the weather station nearest each city.¹ We can’t date the second half, because the normals contain no soil-freeze data.

In most cities the median first frost (32°F) falls near the end of the window, within about a week of the 40°F night. One weather station can’t describe a whole metro area, so a valley, hilltop or lakeshore garden can differ by a week or more. For your own ZIP code, look up your first fall frost date and its odds, then aim to finish planting by about that date.

How the dates compare with local extension calendars

We lined up every local tulip or spring-bulb planting window we could find from extension services against the NOAA dates for the same place.^{5,2,12,13,6,8,10,11,14,15,16,17,18,20}

Three patterns stand out across the 12 fall calendars. The median first frost falls inside 11 of them; Maryland’s October window ends one day before it. The date nights reach 40°F also falls inside 11 of the 12. And the published windows open a median 6 days before nights reach 50°F and close a median 8 to 9 days after they reach 40°F, so the green bars in the chart are a slightly conservative version of what extension services advise.

The night-temperature cue fails in two places, both in Oregon. In Bend, on the high desert, normal lows drop to 50°F by mid-July, and in Corvallis by late August, months before anyone plants bulbs there. Where nights cool early, anchor on the first frost instead: Oregon State’s windows contain the median first frost in both places.¹³

Soil temperature: the cue we can’t map

Clemson’s Home & Garden Information Center says to wait until the soil at planting depth stays below 60°F,¹⁷ and University of Wisconsin–Madison Extension says bulbs can go in when ground temperatures drop to around 50–55°F.²⁴ NOAA climate normals don’t include soil temperature, so we don’t estimate a soil date. If you want to use this rule, push a soil thermometer to bulb depth, 6 to 8 inches, on a few mornings in a row.

Iowa State warns that tulips planted in September, before soils cool, may come up in the fall.⁶ Purdue notes that roots keep forming as long as the soil stays above 40°F, which is why late plantings still work.²³

How much winter cold tulips need

Tulips form their flowers only after a long cool spell. SDSU puts it at 35 to 48°F for 13 to 20 weeks;⁴ Purdue says most spring bulbs need 10 to 13 weeks below 40°F.²³ Without enough cold, Clemson says, bulbs bloom close to the ground on very short stems.¹⁷

Soil temperatures at bulb depth aren’t in the climate normals, and neither are chill hours. As a rough guide we counted, for every ZIP code, the days in a normal winter whose average air temperature is 48°F or colder, the top of SDSU’s range.¹ In 26.6% of 40,563 ZIP codes in the contiguous US there are fewer than 91 such days, the 13 weeks at the low end of SDSU’s range.

Warm-winter gardens: zone 8 is not one climate

Bulb catalogs and Google’s AI Overview sort this advice by USDA hardiness zone: pre-chill in zones 8 to 9 and plant in winter. But the zone map is based on the average annual extreme minimum winter temperature, the coldest night of a typical year, not on how long the cool season lasts.²⁷ When we looked up the 2023 zone for a random sample of ZIP codes,²⁸ 96% of zone 7b ZIPs reached 13 cool weeks, but only 48% in zone 8a, 16% in 8b and 18% in 9a.

The exceptions are in the Pacific Northwest. Seattle and Portland are zone 9a, like Austin, San Antonio and Charleston, but their winters average in the low 40s°F, while those three cities have no days at or below 48°F at all.

How long to pre-chill tulip bulbs

Published chilling times range from 4 to 20 weeks, depending on the source and on whether it means the full cold requirement or the least that still gets a bloom. Google’s AI Overview showed the same split: 6 to 10 weeks for “when to plant tulip bulbs” and 10 to 14 weeks for the zone 8 version of the question.

Sources: UC ANR,²² LSU AgCenter,¹⁸ Texas A&M AgriLife,¹⁹ UF/IFAS,²¹ Purdue,²³ UGA,¹⁶ Clemson¹⁷ and SDSU.⁴ The Gulf Coast advice is the practical minimum for tulips grown as a one-season flower. To meet the longer figures as well, put bulbs in the refrigerator as soon as you buy them in September or October, as Clemson suggests, and keep them there until planting.¹⁷

• Where: the lower part of the refrigerator, not in airtight plastic bags.²⁰
• Away from fruit: apples and other fruits give off ethylene gas that can harm the bulbs.²²
• Plant straight from the fridge: plant immediately after removing the bulbs.²²

Don’t rush chilled bulbs into the ground in November. LSU’s Dan Gill explains why Louisiana waits until late December:

soil that is still too warm can cancel the chilling process

Texas A&M AgriLife gives the same advice for Texas: chill until mid- or late December, then plant.²⁰

How to plant tulip bulbs

Depth advice differs a little by source. Most measure from the base of the bulb:

1. 1

   Pick a sunny, well-drained spot

   Tulips need full or partial sun and well-drained soil.¹⁰ Wet, poorly drained soil rots bulbs during rainy spells, K-State warns.²⁶

2. 2

   Set bulbs point up, in groups

   Place each bulb with the nose up and the root plate down.⁹ Clumps look natural and mean fewer holes: UW–Madison suggests 5 to 8 bulbs per hole, about an inch apart for large bulbs like tulips.²⁴

   

3. 3

   Water in, then mulch

   Minnesota suggests covering the bulbs with half the soil, soaking the area, then adding the rest. Finish with 2 to 3 inches of leaves, wood mulch or clean straw.⁵ If fall is dry, Illinois Extension says to water weekly until the ground freezes.⁸

4. 4

   Feed only if a soil test says so

   Minnesota advises skipping fertilizer unless a soil test shows a phosphorus or potassium shortage, and adding compost instead.⁵ If you use a product, follow its label for the amount.

Most hybrid tulips bloom well for only three or four years, says Cornell; Darwin hybrids, Fosterianas and species tulips last longest.¹⁰ In the warm South, Clemson says tulips can usually be counted on for only one season.¹⁷

Missed the window? Late planting and leftover bulbs

Tulips are the most forgiving bulb for late planting. The University of Minnesota says:

you can plant these as late as you can get them into the soil

Iowa State says tulips can go in as late as December if the soil isn’t frozen,⁷ and Cornell names late November and early December for New York.¹⁰ Plant late bulbs rather than store them: Iowa State finds unplanted tulip bulbs are usually dead by early spring. Its other option is to pot them up and give them 12 to 16 weeks at 40 to 45°F to bloom indoors.⁷

For the rest of the fall garden, see our guides to fall vegetable planting dates, when to plant garlic, when to plant daffodil bulbs and when to cover plants for frost. The flowers and bulbs section collects related guides, our hardiness zone guides explain what zones measure, and the methodology page shows how every frost date here is calculated.