Unusually chilly nights put brakes on tomatoes

A milk jug with the bottom cut off protects a little pepper plant from frost damage. (Photo: Debbie Arrington)

Just when you (and I) thought it was safe to plant our tomatoes, we have an extra-late threat of frost – three weeks after our traditional frost date.

Tuesday’s overnight lows are expected to plunge into the mid 30s. With wind chill, it will feel like 32 degrees in Sacramento – and colder in the foothills.

According to the National Weather Service, storm systems later this week will drop snow as low as 3,500 feet on Wednesday night. And we may have more cold, rainy days this week than we had in all of March.

Following days in the 90s just last week, this cold spell will put on the brakes to rapid spring growth – or kill it all together.

So, what’s a poor tomato plant to do? Huddle up with some temporary protection.

Use a plastic milk or water jug as a mini hot house over a new transplant. Cut out the bottom and leave off the cap. This do-it-yourself “hot cap” will protect the transplant from wind chill and frost danger.

If your tomato plants aren't in the ground yet, wait at least a few more days until the frost danger is past. (Photo: Kathy Morrison)

Strong overnight winds are expected to drive temperatures down to near freezing almost every night this week. So, keep those protective jugs handy. They can be removed during the day (especially if high temperatures heat back up to the high 70s) or left in place.

In the afternoon, deep water tender plants; that extra moisture keeps the ground warm enough to avoid damage. Also, deep water citrus trees, which are now in bloom.

Another precaution: Make sure to mulch your veggies. Those wood chips or leaves act like a blanket over plant roots, keeping them moist and cozy.

Signs of frost damage are already prevalent in Sacramento gardens, due to some unseasonably cold nights in mid March. That chill killed new sprouts and browned transplants as well as burned tender growth on roses and other shrubs that were pushing out shoots.

When temperatures warm up reliably later this month, trim off the damaged foliage from shrubs. Frost-burned transplants may need to be replaced.

Then, it will be time to plant more tomatoes.