What to plant in December in Texas

Worked out for 10 cities from their own weather and frost dates, by zone.

What to sow and plant in December in Texas, by zone: frost possible, highs of 72–82 °F (Brownsville): broad bean, peas, onion, lettuce, carrot and 24 more; frost possible, highs of 61–72 °F (Dallas, Houston and 5 more): broad bean, peas, onion, spinach, lettuce and 21 more; frost possible, highs of 50–61 °F (Lubbock and Amarillo): garlic, broad bean, peas, onion, spinach and 21 more.

In Texas, December is winter.

Frost possible, highs of 72–82 °F: Brownsville

In December, on average, Brownsville has highs of 75 °F and lows of 60 °F, 1.5 in of rain on 7 days; the day lasts 10 h 32 min (on the 15th).

December falls in the frost season: frost-tender crops wait. Average first frost: Brownsville (December 23).

How	What	Where
sow direct	Broad bean, peas, lettuce, carrot, cabbage, broccoli, Swiss chard, beet, parsley, cilantro, arugula, chamomile, chickpea, dill, kale, kohlrabi, mustard greens, parsnip	Brownsville
plant sets	Onion, shallot	Brownsville
start indoors, plant out in February	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	Brownsville
start indoors, plant out in March	Celeriac, celery, chayote	Brownsville

Compared with November: new — carrot, broccoli, tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa and 1 more; no longer sown — cauliflower.

Not starting in December: zucchini (January, started indoors), green beans (February, sown direct) and spinach (no month outdoors by these rules) — dates for Brownsville.

Ready to harvest in December in Brownsville, if sown in the right month: zucchini (October), green beans (October), watermelon (September), pumpkin (August), sweet corn (September), basil (October), arugula (November) and bok choy (October).

Frost dates in Brownsville

Frost possible, highs of 61–72 °F: Dallas, Houston, Austin, San Antonio and 3 more

In December, on average, these cities have highs of 61 to 71 °F and lows of 38 to 55 °F, 0.6 to 6.1 in of rain on 3 to 12 days; the day lasts 10 h 00 min to 10 h 24 min (on the 15th).

December falls in the frost season: frost-tender crops wait. Average first frost: Dallas (December 5), Austin (December 13), San Antonio (December 5), El Paso (December 5) and Corpus Christi (December 23).

How	What	Where
plant cloves	Garlic	El Paso
sow direct	Broad bean, peas, lettuce, carrot, cabbage, broccoli, Swiss chard, beet, arugula, chamomile, dill, kale, mustard greens, parsnip	all
plant sets	Onion, shallot	all
sow direct	Spinach, radish, cilantro, daikon	Dallas, Houston, Austin and 3 more
start indoors, plant out in January	Cauliflower	all
start indoors, plant out in February	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	Corpus Christi
sow direct or start indoors, plant out in February	Parsley	all
start indoors, plant out in March	Celeriac, celery, chayote	all
sow direct or start indoors, plant out in January	Kohlrabi	all
start indoors, plant out in February	Brussels Sprouts	Dallas, Houston and Fort Worth
sow direct	Turnip	Dallas, Fort Worth and El Paso
sow direct	Chickpea	Corpus Christi

Compared with November: new — tomato, bell pepper, eggplant, turnip, chili pepper, Florence fennel and moringa; no longer sown — chicory.

Not starting in December: zucchini (February, started indoors) and green beans (March, sown direct) — dates for Austin.

Ready to harvest in December in Austin, if sown in the right month: zucchini (October), green beans (October), watermelon (September), sweet corn (September), basil (October), arugula (November), bok choy (October) and borage (October).

Frost possible, highs of 50–61 °F: Lubbock and Amarillo

In December, on average, these cities have highs of 55 to 59 °F and lows of 33 to 36 °F, 0.6 in of rain on 3 days; the day lasts 9 h 48 min to 9 h 56 min (on the 15th). A dry month: whatever is sown needs watering.

December falls in the frost season: frost-tender crops wait.

How	What	Where
plant cloves	Garlic	all
sow direct	Broad bean, peas, spinach, radish, cabbage, Swiss chard, arugula, chamomile, daikon, kale, parsnip, turnip	all
plant sets	Onion, shallot	all
sow direct or start indoors, plant out in January	Lettuce, beet	all
sow direct	Carrot, dill, mustard greens	Lubbock
sow direct or start indoors, plant out in February	Broccoli	all
start indoors, plant out in January	Cauliflower, kohlrabi	all
start indoors, plant out in February	Parsley, Brussels sprouts	all
plant bulbs	Crocus, daffodil, hyacinth, tulip	Amarillo

Compared with November: no longer sown — leek, cilantro and chicory.

Not starting in December: tomato (March, started indoors), bell pepper (March, started indoors), zucchini (April, started indoors) and green beans (May, sown direct) — dates for Amarillo.

Ready to harvest in December in Amarillo, if sown in the right month: peas (October), lettuce (October), radish (November), carrot (October), Swiss chard (October), beet (October), pumpkin (August) and parsley (October).

How we work it out

For each city we use its average weather in December and the months after (highs, lows and rain for 2016–2025, ERA5 reanalysis via Open-Meteo) and its average frost dates. A crop starts in December if the month's mean temperature reaches the minimum soil temperature for germination on its card (we use the mean air temperature as a stand-in for the soil's) and if, over its first months (up to three), the average highs stay within its group's range, with no frost for crops that cannot take it. Crops started indoors count from the month they are planted out.

Temperature groups from Colorado State University Extension: cool-season crops prefer 60–80 °F and lose quality in heat; hardy ones grow in days as cool as 40 °F, semi-hardy ones from 40–50 °F (we use 50 °F); warm-season crops need days above 55 °F, and the most tender (tomato, pepper, eggplant, melon, watermelon, squash) above 60 °F, up to 95 °F. Crops the guide does not name go into the stricter group by their frost hardiness. Fava (broad) beans, which the guide does not name, count as hardy: hardy varieties are sown in fall and overwinter (RHS). Garlic and bulbs: a month before the first frost, and later only while the ground is not frozen (as on each city's page).

This is a general rule from averages: your garden can be a week or two earlier or later, and a greenhouse or a cold frame brings the season forward. Greenly works out the dates for your location.