When to Plant Tomatos in Alamosa, CO

Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Alamosa can be reviewed to figure out when you can plant tomatos.


Planting Calendar for Tomatos

Frost tolerance for tomatos: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Tomatos are not cold tolerant which tells us that you have to wait until it warms up after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant tomatos
Possibly ok, but a risky time to plant tomatos
Probably not a good time to plant tomatos

The earliest that you can plant tomatos in Alamosa is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant tomatos and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tomatos may not have a chance to fully mature. Starting your tomatos indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Alamosa. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Alamosa is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Alamosa you get a frost after May 15 be ready to cover your tomatos in the event of a surprise late frost.

USDA Zone Info for Alamosa

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-25°F
Highest Expected Low-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Alamosa

You may be interested in your other planting guides for Alamosa.