The USDA Zone info is a great tool for gardeners to help us estimate 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.

By using the USDA zone info for Modesto you should be able to estimate when it's the best time to plant leeks.

Planting Calendar for Leeks

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

Leeks can survive in a bit of cold which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant leeks in Modesto is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant leeks and expect a good harvest is probably October. You probably don't want to wait any later than that or else your leeks may not have a chance to fully mature. If you are starting your leeks indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Modesto and it is different every year. Since half of the time in Modesto you get surprised by a frost after February 15 be ready to cover your leeks if you have a surprise late frost.

USDA Zone Info for Modesto

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 Modesto

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