Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's possible to plant gladiolus by using the USDA zone info for Cupertino.

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 tend to make it in mild cold which tells us that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant gladiolus in Cupertino 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. If you wait any later than that and your gladiolus may not have a chance to grow to maturity. Starting your gladiolus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Cupertino and it will vary from year to year. Half of the time in Cupertino last frost occurs after February 15 so make sure that you are prepared to protect your gladiolus if you have a late frost.

USDA Zone Info for Cupertino

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 Cupertino

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