One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant welsh onion in Thomson can be figured out by referring to the USDA zone info.

Planting Calendar for Welsh onion

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

You can plant welsh onion just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant welsh onion in Thomson 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 welsh onion and expect a good harvest is probably August. You probably don't want to wait any later than that or else your welsh onion may not have a chance to grow to maturity. You can get started a little bit earlier by starting your welsh onion indoors.

Last Frost Date

On average the last frost is on March 15 in Thomson. In the coldest months of winter you should expect an average low temperature of 10°F.

Always keep in mind that USDA zone info for Thomson is just an average and the actual date of last frost is different every year. Since half of the time in Thomson you get a frost after March 15 be ready to protect your welsh onion if you have one of those late frosts.

USDA Zone Info for Thomson

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Thomson

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