The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant romaine lettuce in Hillsboro should be estimated by looking at the USDA zone info.

Planting Calendar for Romaine lettuce

Frost tolerance for romaine lettuce:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Romaine lettuce are very cold tolerant which tells us that you can start planting them much earlier than other plants that might not handle the cold.

The earliest that you can plant romaine lettuce in Hillsboro 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 romaine lettuce and expect a good harvest is probably September. You probably don't want to wait any later than that or else your romaine lettuce may not have a chance to grow to maturity. You can get started a little bit earlier by starting your romaine lettuce indoors.

Last Frost Date

On average the last frost is on March 15 in Hillsboro. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Hillsboro may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Hillsboro there is a last frost after March 15 so always be ready to cover your romaine lettuce in the event of a late frost.

USDA Zone Info for Hillsboro

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 Hillsboro

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