Rejoicing Amidst the Ninth Month's Lament
Must Summer End So Soon?
Along the Colorado Front Range, there are some years when we can get to October before we experience our first freezing temperatures. It is not often.
We Know Winter's Coming
Temperatures take a turn at this time of year, and just like school students who must leave summer behind and return to the classroom, so a similar lament rises in the heart of the gardener (at least this one) as we enter the month of September. Although we enjoy some of the finest weather of the year this month, we know the frost/freeze likely will come in September to deal death to all of our unprotected summer crops.
What Will You Do?
Maybe you’ll try to protect your sensitive plants with a horticultural (or other) blanket to keep them alive. It can work. But even if you do save them with a blanket, they still will not grow much because of the cool temperatures and waning solar energy. If you keep a horticultural blanket over them day and night, they will do better since the low temperature they will experience will not be as severe. And although the horticultural blanket diminishes a bit of the light coming through, it diffuses our harsh Colorado sun in such a way that plants do very well under them. Once a plant feels a certain frigid temperature, it will stop growing or making fruit. The blanket adds days to the calendar before your plant will experience this.
When to use a blanket
Leave your windows open all night and sleep without any covers. If you wake up feeling frozen, know that your plants are feeling the same. It’s harder to get going in the morning if you first have to thaw out. Same for your plants. Some of them won’t get going until sundown. Hence, your plants stop producing even though they are still alive. With the horticultural blanket on them, they’ll stay warm and toasty (or at least a few degrees warmer than the outside air), extending your ability to harvest fresh produce.
The Final Hours (or Days) Before the First Frost or Freeze
As often as not along the Colorado Front Range the frost or freeze will be preceded by amazingly warm weather. This year (2020) is a perfect example. We are forecast to see 98°F on September 5 & 6. September 7th is the day the shock comes. High of 85°F with a low of 35°F. Then comes the hammer the next day, the 8th, when the high will be only 37°F with a low of 28°F. Unless your garden area is at a lower elevation or naturally protected, or you cover them with a blanket, your summer plants will be killed.
If you are not going to bother with blankets, here’s what I suggest:
- Harvest all tender summer crops while it is still warm. The cold will wound them. Get them inside your house before the cold snap. These include:
- Annual flowers
- Basil or other annual herbs
- Fruits (soft summer fruits) like cantaloupe/muskmelon
- Tomatillos
- Tomatoes – take them even if they are green. Put the green ones in a paper bag or cardboard box and they will ripen over time.
- Zucchini (or other summer squashes)
- Harvest part of each cold tolerant plant that could be damaged by the cold and snow load.
- Leafy greens of a size that can be damaged by the weight of the snow and/or wind accompanying the storm.
- Leave about 1/3 to 1/2 of each plant to continue growing after the storm.
(Side Note on Draining the Irrigation System)
Though there is plenty of latent heat in the ground and structures to help prevent a hard freeze on your piping and hoses, I prefer a ‘better safe than sorry’ approach regarding when to drain my sprinkler system or detach hoses from the spigots. It takes 5 minutes for me to drain my sprinkler feed to the vacuum breaker and valve box, push the “Water All Zones Now” button on my controller (allowing air into the sprinkling lines going from the valve box, so each zone can drain), and disconnecting all hoses from the side of my house to be sure the spigots can drain.
I will almost always re-pressurize the system after this first frost event, if we have weeks of warm weather in the forecast.
It’s Sad, But Be Happy
Yes, it marks the end of summer. The landscape changes. We see death where there was life. But look at all the produce you have brought in to enjoy with your friends and family! Be grateful for the bountiful crop and its most excellent quality.
As you clear away the dead vines and stalks and put them in your compost bin, draw out the mature compost like an aged wine and spill it out upon the garden beds to enrich the earth and cheer the living creatures within it. As the temperatures of September alternate between summer and winter, spend time outside pondering the magnificence and munificence of it all!