One of the first steps you take when you are estimating 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.

It's possible to estimate when it's the best time to plant hypericum by checking out the USDA zone info for London.

Planting Calendar for Hypericum

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

You can plant hypericum a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant hypericum in London 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 hypericum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your hypericum may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your hypericum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in London. It might get as low as -10°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for London and it can change quite a bit from year to year. Half of the time in London last frost occurs after April 15 so make sure that you are prepared to cover your hypericum in the event of one of those late frosts.

USDA Zone Info for London

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in London

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