The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant catharanthus in Astoria should be determined by referring to the USDA zone info.

Planting Calendar for Catharanthus

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

It's probably a bad idea to plant catharanthus until after the last frost when the weather gets warmer because they require warm weather.

The earliest that you can plant catharanthus in Astoria 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 catharanthus and expect a good harvest is probably August. Any later than that and your catharanthus may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your catharanthus indoors.

Last Frost Date

In Astoria the average date of last frost happens on March 15. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Astoria may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Astoria it frosts late in the year after March 15 so make sure that you are prepared to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Astoria

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

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

Plants to Grow in Astoria

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