When to Plant Garlic in Texas: Counting Back From the First Frost

Garlic goes into Texas soil in fall, not spring. Growers counting back from Houston’s first fall freeze, which NOAA’s National Centers for Environmental Information puts between December 1 and December 19 in its 1991-2020 climate normals at the IAH station, land on a set-out window running from early November to late November. That gives cloves roughly three to seven weeks to root before the ground cools past the point where roots keep growing. Get cloves in the ground within that window rather than waiting for a freeze to tell you it’s time, and check your own county’s frost data before assuming Houston’s dates apply to your yard.

The short answer for Texas

Cloves planted in a warm October rot before they root, soft and yellow by Christmas instead of anchored and green. Wait too long chasing that softness away, and a hard freeze catches them barely set, heaved out of loosened soil by the first real cold snap. Both failures trace back to the same mistake: picking a date off a calendar instead of off your own ground. Houston’s freeze window moves year to year, and garlic planted against the actual season, not an assumed one, is the difference between a full head next June and a handful of stunted cloves.

Count backward from the freeze window and you get the November range growers actually use. Cloves set out in early November have close to seven weeks to root before the earliest date in that freeze window arrives. Cloves held to late November get closer to three weeks before the latest date in the window arrives. Either end works, since garlic roots keep growing in cool soil after topgrowth stalls, and Houston’s ground rarely freezes hard enough to stop root activity outright.

Treat December 1 to December 19 as a midpoint, not a deadline. NOAA’s freeze probabilities put that window at the 30 to 70 percent band, which means in roughly half of all years the first hard freeze lands later than December 19, and in plenty of others it lands earlier. Planting on the calendar rather than watching your own season is how gardeners end up racing a freeze that arrived early, or leaving cloves in warm soil for weeks longer than needed. A wet, warm October pushes the safe planting date later than a dry, cool one, so read your own fall before you commit to a week.

Every variety above shares the same set-out window, because that window is set by the freeze date, not the cultivar. What differs is how each type performs afterward: softnecks like Inchelium Red and Lorz Italian need little winter chill and cure reliably here, while hardnecks such as German Red, Duganski, and Chesnok Red want cold this climate mostly doesn’t supply. For the full breakdown of that trade-off, see Garlic Varieties That Suit Texas Winters.

Working it out for your own garden

The arithmetic behind the window

The method is the same wherever you garden in Texas, even though the dates change. Start with your area’s first fall freeze date, then count backward the three to seven weeks garlic needs to grow roots before cold shuts growth down. The wider that gap, the more slack you have to plant early without pushing top growth into a freeze, or late without leaving cloves rootless when the cold arrives.

Near Houston that math runs like this: NOAA’s NCEI 1991-2020 normals put the first fall freeze at the IAH station between December 1 and December 19. Subtract seven weeks from December 1 and you land in mid-October. Subtract three weeks from December 19 and you land in late November. Growers split the difference and settle on early to late November, favoring the later half of that range if the fall has stayed warm and the soil is still holding summer heat.

What moves the date away from Houston’s

Houston itself is not one climate. Hobby Airport, closer to the coast, runs about two weeks milder than the IAH station used for the figures above. A garden near Hobby can hold off planting into the back half of November without much risk, while a garden further inland from the coast’s moderating effect may see its own first freeze arrive earlier than the Houston range suggests. Before you plant, make sure the bed is prepped the way Growing Garlic in Texas describes, with soil worked loose enough for roots to run once they start.

The same local features that shift frost dates anywhere else in the country apply here too. Elevation, a large lake, and closeness to the coast can each move a local freeze date by roughly two weeks in either direction from what a regional station reports. A garden set in a low frost pocket away from any water tends to freeze first. A garden buffered by a lake or bay, or sitting on a rise where cold air drains away, tends to hold off longer. None of this shows up in a single station’s normals, which is why the Houston figures above are a starting point, not a verdict on your own yard.

Soil type changes the math too. Heavy clay retains moisture and cools slowly, giving roots a longer working window at the same air temperature. Sandy soil drains and cools faster, so cloves planted on the same date root less by the time a freeze arrives. Water in a new planting and hold off on mulch until roots have had a week or two to start, especially if you’re planting toward the early edge of the window into soil still holding summer heat.

What changes across Texas

Every number above comes from one station in Houston, and Texas spans four USDA hardiness zones, so no single planting window covers the state. The Panhandle sits at the cold end of that range. Its growing season closes months earlier and reopens months later than the Gulf Coast’s, which means a Panhandle grower working from a first-freeze-based window needs that region’s own frost data, not Houston’s, checked against TAMU AgriLife Extension’s county figures before planting.

Hill Country and North Texas fall somewhere between the two extremes, with elevation and distance from the Gulf’s moderating humidity pushing their first freezes earlier than Houston’s December 1 to December 19 range. A grower in either region who plants on the Houston calendar risks setting cloves out several weeks too late, since the same three-to-seven-week rooting window then runs up against a freeze that has already arrived.

The Gulf Coast itself is not uniform either. Coastal counties close to the water hold Gulf-moderated warmth longer into fall than counties even a short distance inland, and Houston’s own Hobby Airport station runs about two weeks milder than the IAH station used for the figures in this piece. A gardener near Galveston Bay or the immediate coastline can generally afford to wait toward the back end of the November window, while one further inland, even within the greater Houston area, should lean toward the earlier weeks. None of this substitutes for a local number. If you garden outside the Houston area, the calculation in the previous section still works, it just needs to start from your own county’s first freeze date rather than the one printed here for IAH.

The mistakes this climate punishes

Betting on cold that doesn’t arrive

The single costliest mistake here is planting a hardneck garlic and expecting a Texas winter to do what a Vermont winter does. Garlic needs several weeks of cold below 40°F after planting to trigger the split into cloves, and the University of Georgia Extension puts that requirement at six to eight weeks. Measured at the Houston station used throughout this piece, the growing season spends zero weeks below 40°F. Hardneck varieties such as German Red or Duganski can still be grown near Houston, but expect smaller, less reliably divided bulbs than a softneck like Inchelium Red or Lorz Italian, which needs far less chilling to perform well.

Wet soil and disease pressure

The second mistake is treating a mild winter as a safe winter. UC IPM’s Pest Management Guidelines for Onion and Garlic (UC ANR Publication 3453) show why. These figures come from monthly average air temperatures at the same Gulf Coast station used throughout this piece, not soil measurements and not a statewide survey, so read them as a seasonal pattern rather than a local forecast. White rot, caused by the fungus Sclerotium cepivorum, has a published range of 50-75°F, and this station’s growing-season air temperature falls inside that range for seven months, October through April, including two months at the disease’s own optimum. Fusarium basal rot, caused by Fusarium oxysporum f. sp. cepae, has a published range of 59-90°F that overlaps eight months of the Texas garlic season. Pink root, caused by Setophoma terrestris, has a published optimum of 75-85°F that this station’s air temperature matches in four months, all four of them at that optimum. Southern blight‘s optimum runs hotter still, 86-95°F, a range this station’s growing-season air temperature never reaches on average, which lowers the disease’s activity here without ruling it out.

None of these figures mean a disease is guaranteed. They compare air temperature against thresholds published for soil, soil lags behind air and swings less, and a single month’s average hides plenty of days on both sides of it. What turns the risk real is planting into heavy, waterlogged ground during those months, or reusing cloves from a bed that has carried onions or garlic before. Raised beds and clean seed stock matter more here than in a drier climate.

Planting too shallow, too early, or too late

Cloves set only an inch deep can heave out of loose, wet soil during a soggy winter, and cloves planted before the ground has cooled from summer heat can rot before they root at all. Held past the end of the November window into December, the reverse problem shows up: not enough time left to root before whatever freeze does arrive, hard or not.

Checking this against your county

Every date in this piece is built from one weather station near Houston, and your county’s own numbers may run a week or two earlier or later, or considerably more if you garden outside the Gulf Coast entirely. TAMU AgriLife Extension keeps county-level agents and horticulture publications that track local frost data more closely than any statewide figure can. Check with your county’s office, listed through the TAMU AgriLife Extension directory, before locking in a planting date, especially if you garden in the Panhandle, Hill Country, or anywhere north of the Houston area covered here.

Common questions

Can I Plant Garlic in Texas in spring instead of fall?

Not with any reliability. Garlic grown for bulbs needs the fall-to-summer cycle to build root and leaf mass before it divides into cloves, and a spring planting near Houston leaves too little cool-season growth before summer heat pushes the plant toward early, undersized bulbing.

What happens if I miss the late-November cutoff?

You can still plant into early winter, but the crop takes the hit rather than the calendar. Cloves set out late root for fewer weeks before growth slows, which generally means smaller bulbs at harvest rather than a failed crop outright, especially with a softneck variety that needs little chilling to begin with.

Should I refrigerate garlic cloves before planting them here?

Some growers pre-chill hardneck seed cloves for several weeks in the refrigerator to make up for the chilling a Houston winter doesn’t reliably provide. It can help hardnecks size up, but it does not fully substitute for weeks of real cold in the ground, so a softneck variety remains the more dependable choice for this climate.

My town isn’t near Houston. Does this window still apply to me?

Use the method, not the dates. Find your own area’s first fall freeze range through TAMU AgriLife Extension or NOAA’s climate normals, then count back the same three to seven weeks described above. The further you are from the Gulf Coast, especially toward the Panhandle or Hill Country, the earlier your own window is likely to fall.