One of the first steps you take when you are making a decision about 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.

A way of getting a good idea when to plant gladiolus is to refer to the USDA zone info for San Mateo.

Planting Calendar for Gladiolus

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

Gladiolus do ok in moderate cold which tells us that you can get them planted just a bit earlier than other plants that might not handle the cold.

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

Last Frost Date

In San Mateo the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

Always keep in mind that USDA zone info for San Mateo may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in San Mateo it frosts late in the year after January 31 so be sure to be ready to protect your gladiolus if you have a late frost.

USDA Zone Info for San Mateo

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in San Mateo

You may be interested in your other planting guides for San Mateo.