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.

By reviewing the USDA zone info for Lansdale it's a good idea to estimate when it's possible to plant welsh onion.

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 are barely cold tolerant which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant welsh onion in Lansdale 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 fully mature. You can get started a couple of weeks earlier by starting your welsh onion indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Lansdale. In the coldest months of winter you can expect an average low temperature of -5°F.

Just be sure to remember that USDA zone info for Lansdale is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Lansdale you get surprised by a frost after April 15 be ready to cover your welsh onion if you have a surprise late frost.

USDA Zone Info for Lansdale

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Lansdale

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