Bellingham — As the first day of fall arrives on September 22, the first frost of the year is not long in coming, which could damage your hanging baskets and your garden.
The Farmers’ Almanac has predicted the first frost for four of Washington’s cities by finding the normal average date of the first frost.
According to the almanac, the first freeze will first hit Spokane on October 3. Olympia will follow on October 6th and Vancouver will likely get its first freeze on October 15th. Seattle is expected to have its first freeze about a month later. on November 17.
These dates are supposed to bring a light frost between 29 and 32 degrees. This cold will kill tender plants such as cucumbers, squash and tomatoes and will have “little destructive effect” on other vegetation, according to the almanac.
Moderate frosts between 25 and 28 degrees cause serious damage to flowers, tender and semi-rigid plants, and have a destructive effect on most vegetation. Severe frosts below 24 degrees damage most plants, warns the almanac.
The Old Farmer’s Almanac, an almanac that began in 1792 and is updated annually, predicted the first frost by city.
This is when the Old Farmer’s Almanac predicts your first frost:
Bellingham, October 26.
Olympia — October 6.
Pasco — October 25.
Richland, October 18.
Spokane, October 7.
Lynden, October 16.
Ferndale, October 23.
How to protect your plants from frost
The Old Farmer’s Almanac also offers tips for keeping your plants safe from frost damage and lists critical low temperatures for each plant when frost will damage plants.
Carrots, peas and potato tubers have a critical temperature of 28-30 degrees, where they will start to get damaged by freezing weather. Tomatoes, sweet corn, sweet potatoes and watermelon have critical temperatures from 32 degrees and are considered tender plants.
The Old Farmer’s Almanac advises you to cover your garden with nonwoven polyester row covers or medium-weight sheets, tarps, or fabrics to protect them from frost.
Local nurseries can also offer tips and resources to keep your plants safe in the cold. Paige Lanham, owner of Garden Spot Nursery in Bellingham, WA, says that one of the best ways to protect your plants is to cover them with mulch.
“Making a 1-2” deep donut ring of mulch or compost around plants, especially those planted this year, can help protect them from cold weather. This will protect them and feed the soil around them… Planting in the ground will keep a plant warmer than planting in a pot, but if a plant is in a pot, it can be moved to the garage or near the house for a cold snap,” Lanham wrote in an email to McClatchy.
Lanham also suggests wrapping a pot in bubble wrap to insulate it, warning about the extra moisture that winter frost and snow can bring:
“Wet soil in the PNW in the winter can also be a killer, so making sure you plant in areas that have good drainage and adding a little compost while you plant can help your plants survive as well,” Lanham wrote. .
Here are some ways you can prevent frost from damaging your plants and your Homes and Gardens garden:
• Do not keep potted plants outdoors during the winter months.
• Insulate your plants and garden with extra mulch before temperatures drop.
• Move your tender plants to a protected area.
• Water the plants in the morning.
• Wrap larger plants and pots to keep them warm if you can’t move them inside.