Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Smithville should be used to determine when it's a good idea to plant watercress.

Planting Calendar for Watercress

Frost tolerance for watercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Watercress can survive in a tiny bit of cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant watercress in Smithville is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant watercress and expect a good harvest is probably August. Any later than that and your watercress may not have a chance to grow to maturity. Starting your watercress indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Smithville the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Smithville is just an average and the actual date of last frost is different every year. Half of the time in Smithville there is a last frost after April 15 so always be ready to cover your watercress if you have a late frost.

USDA Zone Info for Smithville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Smithville

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