Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Alton you can determine when it's possible to plant salsify by looking at the USDA zone info.

Planting Calendar for Salsify

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

Since salsify are one of those plants that can tolerate a tiny bit of cold weather you can plant them just a tiny bit earlier in the year than other frost tender plants.

The earliest that you can plant salsify in Alton 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 salsify and expect a good harvest is probably August. Any later than that and your salsify may not have a chance to grow to maturity. Starting your salsify indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Alton the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Alton 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 Alton it frosts late in the year after April 15 be ready to cover your salsify in the event of a surprise late frost.

USDA Zone Info for Alton

Here is the info for USDA Zone 6a.

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

Plants to Grow in Alton

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