Let It Frost

October 2015

Pickaway to Garden

 

Let It Frost

 

By Paul J. Hang

 

Blue Jays have been showing themselves in the yard lately. After spending the summer out in the hinterlands they have been invading the city for the ripening acorns and preparing to mob our feeders . These noisy beautiful relatives of crows perform security duties in the woods alerting its inhabitants when one of us enters their territory. I have heard them screaming and it sounded a little like “Freeze.” Let’s hope they are simply being prematurely alarming.

 

If we haven’t experienced it by the time you read this, frost should be happening soon. Average date of first frost is October 20^th here in South Central Ohio. That means that there is a 50/50 chance of frost occurring by that date. Chances are less before that date, more later. Usually we get a couple days of frost in a row followed by Indian Summer which can last for several days. If we protect our susceptible plants from the first freezing temperatures we can often get 3 to 5 more weeks of blooms and vegetable production.

 

The occurrence of frost can be variable. Frost is more likely to form on clear starlit nights without the warming cover of clouds. Because cold air is more dense than warm air, in calm weather cold air pools at ground level. This is why frost is more common and extensive in low lying areas. If your plants reside in one of these “frost pockets” you may experience frost damage even if the forecasters aren’t calling for frost. In addition, the official temperature is taken at 5 feet above ground level. The official temperature could be 36 degrees while the temperature at the ground could be 32 degrees. There is also no truth to the saying that frost is more likely during a full moon.

 

The effect of frost can also be variable. Plants range from tender to hardy. Tender plants like tomatoes, beans and lettuce, impatiens, marigolds and zinnias tolerate no frost at all. Hardy plants like members of the cole family such as cabbage and Brussel sprouts, beets and pansies are less susceptible. Two things we can do to protect plants from freezing are to cover them and to irrigate before frost. Covers are more effective if they don’t touch the plants. Woven covers are better than plastic or paper and are best applied in the late afternoon when frost is forecast. Watering the garden before frost also helps. If it gets cold enough to break plant cell walls wilting and death will occur in affected tissues.

 

If the Jays are right in their prediction, the gardening season is over, kaput! A hard freeze that will kill annuals and the vegetation of perennials is temperatures as low as 26 degrees for several hours. Freezing temperatures bring a change that most gardeners welcome, an end to gardening. I must confess to a sense of relief when the growing season ends. Admittedly the work doesn’t necessarily end, there are still chores that should be done, but you can quit if you want to. Let it frost.

 

Things to do in the garden:

 

Hot caps and covers should be made handy in case a frost or freeze is forecast. Remember that the coldest temperature usually comes a little after sunrise. The earth radiates heat away and the sun hasn’t climbed high enough to begin heating us. You might still save some plants even if you slept in after it became light.

 

Consider bringing in the houseplants that you put outside this summer if you haven’t already. Make sure you don’t bring in any bugs with them; a good blast of water from your hose can wash most of them off. Bring the pots into a sheltered spot for a week or so to help the plants acclimate before shocking them with the warmer temperatures of your home.

 

In October, and even into early November, plant garlic and shallots. Cloves from store bought garlic may not work as some are treated to delay sprouting. You can also order favorite varieties from seed catalogs. Separate the cloves and plant 4 inches apart. Harvest garlic around the 4^th of July.

 

Dig up your tender corms and bulbs as soon as they are frostbitten. Dahlias, glads, tuberous begonias and cannas should be dug and stored in a cool dry place. Most basements are too warm. Caladiums should be stored at  65-70 degrees. Go to ohioline.osu.edu and bring up Factsheet HYG-1244-92 to get specific information on storing Summer Flowering Bulbs.

 

You can still divide day lilies and iris. Cut back the iris leaves to four-inch fans. Stop feeding your roses but don’t stop giving them water. Consider cutting back your roses halfway if they stop blooming. If you have dormant roses you can still plant them.

 

Spring bulbs can be planted as soon as you get them. Plant them at a depth three times their length; place some bulb food in the hole with them. For a better display plant them in groups, not single file.

 

If you planted trees this year protect the trunks from gnawing rabbits and other varmints with hardware cloth or the plastic wrap made for this purpose. Even older trees can benefit from this if you’ve experienced this damage in the past.

Continue to water trees and shrubs planted in the past couple years.

 

If you don’t accumulate a lot of leaves consider just shredding them with the mower and leave them scattered on the lawn. Otherwise, compost them. It is still the best time to fertilize your lawn. Use a high nitrogen soluble product. You can still sow grass seed.