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When to Plant Platycodon in Castle Rock, CO

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 platycodon in Castle Rock should be determined by referring to the USDA zone info.


Planting Calendar for Platycodon

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

Platycodon do ok in moderate cold which tells us that you can plant them slightly earlier than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant platycodon
Possibly ok, but a risky time to plant platycodon
Probably not a good time to plant platycodon

The earliest that you can plant platycodon in Castle Rock is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant platycodon and expect a good harvest is probably August. You probably don't want to wait any later than that or else your platycodon may not have a chance to really do well. If you are starting your platycodon indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Castle Rock. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Castle Rock and it can change quite a bit from year to year. Half of the time in Castle Rock it frosts late in the year after April 15 so just be sure to be ready to protect your platycodon if you have a surprise late frost.

USDA Zone Info for Castle Rock

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°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 -10°F.

Plants to Grow in Castle Rock

You may be interested in your other planting guides for Castle Rock.