When people think about planting and harvesting crops, they usually think about doing it in warm weather. After all, these are typically optimal conditions for plants to be able to survive and thrive. However, some people might wonder if plants can survive colder conditions.
Can zucchini survive frost? Zucchini is a warm-season crop and should not be planted until after the danger of frost has passed. If you are located in an area where late frosts are typical, you should wait for the threat of frost to have passed before you plant zucchini. A late frost could ruin your plants, but there are damage control measures you can take to save your zucchini crop.
Regardless of whether you are a savvy gardener who always plants after the frost date, or a newbie not sure how to determine the frost date, Mother Nature has a way of surprising us. Let us help you save your zucchini.
How Does One Protect Zucchini from Frost?
There are certain crops that can tolerate a little bit of frost. These include peas, cabbage, parsnips, and carrots. However, zucchini is a warm-season crop. Cold temperatures can do damage to zucchini plants.
If you happen to be in a region where you get late frosts, you’ll need to protect the zucchini from them. Ideally, you should wait for it to pass before you plant zucchini. However, predicting frost is more art than science, and sometimes you’ll end up with zucchini in the ground before the last frost has passed.
In these situations, you can cover the zucchini plants with different items. These include old sheets, plastic, newspapers, and straw. What you’re trying to do here is trap the heat in the soil into the air that immediately surrounds the plants, rather than letting it float away into the surrounding cold.
Also, you don’t want these items to be making direct contact with your zucchini. Use stakes to keep material, particularly plastic, from touching the foliage of your plants. The best strategy is to cover up your zucchini plants at night and remove the coverings in the morning. If you leave the coverings on throughout the day, they could end up trapping the sun’s heat – ultimately killing your zucchini.
While these tactics can be effective, you should keep in mind that they are only going to be useful if you have a very short and very mild frost. They likely won’t save your zucchini from hard freezes or long term cold temperatures.
If you are new to gardening or have recently moved, there are several guides that can help you determine what the frost dates will be. Check out the USDA Plant Hardiness Zone Map here. In addition, microclimates, or the small variations in climate based on your yard, can also affect your plants. Use this planning guide to help you determine what microclimates exist around you.
In case an extremely late frost occurs, and your plants already have fruit on the vines, you’ll need to harvest them right away.
Why Is Frost So Harmful to Plants?
You might wonder how and why exactly frost can be harmful to plants. You know that overly cold temperatures can cause hypothermia in people, but plants don’t work in exactly the same way. In the case of plants, frost is harmful because it can cause ice crystals to form within plant cells.
This can be very dangerous for plants since it makes water unavailable to plant tissues. It can disrupt the movement of fluids within plants. When you see leaves that look water-soaked, shriveled, and dark brown and black, you probably have leaves that have been damaged by frost.
However, plants have different levels of tolerance towards frost and cold temperatures. “Hardy” plants can tolerate short-term freezing to some extent, while “tender” plants can be injured or even killed by freezing temperatures and frost. Zucchini is a relatively tender plant. The University of California Division of Agriculture has more information about frost tolerance here.
Preventative Measures for Frost Damage
When it comes to planting zucchini and the time of the last frost, there are certain things you can’t control. However, there are certain things you can do in order to minimize the chance that your zucchini will be damaged by frost.
First of all, when you’re planting the zucchini, avoid doing so in open and exposed areas. Also, do not plant it in low spots where cold air will tend to settle. You want to plant zucchini in areas that will be protected from the cold, and close proximity of other plants or structures can be beneficial.
The best place to plant zucchini would be near a west- or south-facing wall, which will absorb heat during the day and radiate heat at night. Planting zucchini around a boulder, fence, or shrub can also be an excellent protective measure. It would be a good idea to cluster any container plants close together and plant them in a sheltered spot close to your home if possible.
Once you have planted the zucchini, there are other things you can do. For example, you can water the soil thoroughly. Wet soil will hold heat better than dry soil does; it can protect roots and warm the air near the plant.
You can also place a 100-watt lamp that is designed for outdoor use in the interior of a small tree nearby. It can emit a small amount of warmth, which can minimize frost damage. Alternatively, you can use holiday lights, as long as they are not LED lights. Just make sure that the lights don’t make contact with any material that you’re using to cover up the zucchini.
Another good idea may be to spray an anti-transpirant on the foliage of zucchini and other cold-sensitive plants. This can seal in moisture. One application of an anti-transpirant can protect your plants for up to three months by coating them with an invisible polymer film. There are many such products available, such as this one on Amazon.
You should also know that plants are more resilient than you would usually expect. If you see that your zucchini has some frost damage, you don’t need to dig it up right away. Wait until the weather warms up to see if new leaves start to sprout. It’s possible that you’ll have new regrowth at the base of the plant, and then you’ll be able to prune out the damaged parts.
What Should One Do with Mature Zucchini in a Frost?
If you have mature zucchini plants, you should harvest them now and wipe them dry. Then, you should cure them in a hot, dry room for a few days. Don’t store the zucchini on metal or concrete surfaces. This can lead to them rotting prematurely.
This would also be a good idea with pumpkins, squash, and cucumbers.
Final Thoughts
It’s always good to have a solid understanding of the plants that you are trying to grow and harvest. You should also know how to handle different sorts of obstacles that might come up, such as an unexpected frost.
It won’t always be possible to salvage your plants in this situation. However, you can definitely try, and sometimes it will work. You just need to know the best techniques to be able to preserve your zucchini and other plants that might be affected by the frost.
Temperature is only one of the laws of plant growth. Be sure to brush up on the rest in this brief article before you go.
If you understand a little bit about plant biology and how to protect each of your plants, you are more likely to have a successful harvest. And a bountiful harvest is what we want after all. Otherwise, might as well plant some grass.