One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. 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 Collingswood can be read to determine when it's the best time to plant zinnia.

Planting Calendar for Zinnia

Frost tolerance for zinnia:	Not tolerant of frost.
When to plant:	After the last frost.

It's not a good idea to plant zinnia until after the last frost because they are not cold tolerant.

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

The last month that you can plant zinnia and expect a good harvest is probably August. If you wait any later than that and your zinnia may not have a chance to grow to maturity. If you are starting your zinnia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Collingswood. In the coldest months of winter you can expect an average low temperature of 0°F.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Collingswood and it can change quite a bit from year to year. Since half of the time in Collingswood there is a last frost after April 15 be ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for Collingswood

Here is the info for USDA Zone 7a.

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

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Collingswood

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