One of the first steps you take when you are determining 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 Helena can be reffered to in order to figure out when it's a good idea to plant swan river daisy.

Planting Calendar for Swan River Daisy

Frost tolerance for swan river daisy:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You really shouldn't plant swan river daisy until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant swan river daisy in Helena is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant swan river daisy and expect a good harvest is probably August. Any later than that and your swan river daisy may not have a chance to grow to maturity. If you are starting your swan river daisy indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Helena. In the coldest months of winter you can expect an average low temperature of -25°F.

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 Helena and it is different every year. Since half of the time in Helena you get surprised by a frost after May 15 be ready to cover your swan river daisy in the event of 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.