One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Helena you can figure out when it's a good idea to plant veronica by using the USDA zone info.

Planting Calendar for Veronica

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

Veronica can survive in a little bit of cold which means that you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

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

Last Frost Date

The average date of last frost is May 15 in Helena. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Helena may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Helena last frost occurs after May 15 be ready to cover your veronica if you have one of those late frosts.

USDA Zone Info for Helena

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Helena

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