Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Portland you can estimate when to plant lemon grass by referring to the USDA zone info.

Planting Calendar for Lemon grass

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

Lemon grass do ok in mild cold which tells us that you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant lemon grass in Portland 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 lemon grass and expect a good harvest is probably September. If you wait any later than that and your lemon grass may not have a chance to grow to maturity. If you are starting your lemon grass indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Portland may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Portland there is a last frost after February 15 be ready to protect your lemon grass in the event of a late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in Portland

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