Before planting it is a good idea to find your USDA Zone info to figure out 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.

One way of figuring out when you can plant welsh onion is to use the USDA zone info for Marlow.

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.

Welsh onion do well in mild cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant welsh onion in Marlow 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. If you wait any later than that and your welsh onion may not have a chance to grow to maturity. If you are starting your welsh onion indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Marlow the average date of last frost happens on April 15. You can expect an average low temperature of 5°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Marlow and it will vary from year to year. Since half of the time in Marlow you get a frost after April 15 be ready to protect your welsh onion in the event of a surprise late frost.

USDA Zone Info for Marlow

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Marlow

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