One of the best tools that you have as gardeners to help us figure out 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.

In Oshkosh you can determine when you can plant asters by checking out the USDA zone info.

Planting Calendar for Asters

Frost tolerance for asters:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant asters a little earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

The last month that you can plant asters and expect a good harvest is probably September. Any later than that and your asters may not have a chance to fully mature. If you are starting your asters indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Oshkosh the average date of last frost happens on April 15. It might get as low as -20°F during 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 Oshkosh and it can change quite a bit from year to year. Half of the time in Oshkosh there is a last frost after April 15 so make sure that you are prepared to protect your asters in the event of one of those late frosts.

USDA Zone Info for Oshkosh

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Oshkosh

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