Tips for growing hot peppers in cold climates

By Sam Schipani, Bangor Daily News Staff

Hot peppers are a fun, spicy addition to any garden. But their long growing season and specific growing conditions make hot peppers difficult to grow in a chilly place like Maine. With a few extra steps, though, it is possible to add hot peppers to your garden — and help them to thrive.

The primary challenges to growing hot peppers in Maine are temperature and weather.

“Many of the most flavorful hot peppers take a very long time to mature, and without a way to protect them through the season, they just can’t make it,” said Amy LeBlanc, owner of Whitehill Farm in East Wilton. “In addition, peppers, especially hybrids, can be very picky about the optimum temperature for setting fruit. Yes, they are fun to grow, but [they] can be tricky to grow well.”

Why go through the trouble of growing hot peppers at all? First — and perhaps obviously — you may think about growing hot peppers if you like spicy food.

“Hot peppers are trendy, and for several reasons,” LeBlanc said. “Primary for me as a grower is to enjoy them in my food and be able to tell people how hot they are. We use ours fresh and dried in many dishes year round.”

LeBlanc said that on her farm, she also uses hot peppers for value added products, like decorative hanging ristras as well as handcrafted spices like chili powder and paprika. 

Eric List, owner of Morning Glory Farm in Bethel, started growing hot peppers for hot sauce around five years ago.

“It’s been a blast,” List said. “We learn something new every year. It’ll probably be a couple years before we have our list of best practices all together, but we’re getting better at it. It is kind of an odd crop to grow in the region we’re growing, but I happen to be a hot sauce fanatic and it’s really fun to play around with that.”

Choose varieties wisely

If you are growing hot peppers in a cool climate, opt for hot peppers with a shorter growing season.

“We like early jalapeno, cayenne, poblanos and Hungarian hot wax, as they seem to ripen reliably in Maine,” said Mary Margaret Ripley, co-owner of Ripley Farm in Dover-Foxcroft. 

LeBlanc has her favorites as well. 

“Czechoslovakian black is an early and very adaptable variety, about as hot as a jalapeno, and it will bear all season,” LeBlanc said. “Thai hot is very small, also adaptable and very hot.  They dry real well making this a good candidate for keeping for the winter. Long red cayenne is as hot as its name implies, and if it is potted, can be brought in for the winter and it will continue to make peppers.” 

LeBlanc also recommended Matchbox peppers for pickling, Big Jim for a milder heat and Hot Paper Lantern for something spicier without the long, finicky growing season of traditional habañeros. 

List said that many of the varieties that grow well in Maine are not the hottest ones.

“We grow about eight or nine varieties of peppers and most of them are relatively mild,” List said. “We grow them for their flavor mostly. Then we grow some peppers specifically for their heat. We grow a lot of habaneros and we grow some ghost peppers. For us, they grow much slower generally. The hotter they are, they seem to be on shorter bushy plants [and] the peppers are smaller.”

Start seeds inside

If you are starting hot peppers from seed, you have to do so indoors before transplanting them outside in a cool climate like Maine’s.

“We start our peppers from seed to create seedlings to sell and then plant quite a number of them ourselves,” LeBlanc said. “The list of seed [starting] stuff is pretty standard: pots that are large enough to see a seedling to a good size for transplanting; a good potting mix that is not too fertile; good light to prevent legginess; warmth to speed growth.”

You could also use heat mats to promote the proper warmth of your hot pepper seedlings or get creative and put them in warm spots in your house.

“We have a very warm utility room that has a hot water tank and we use the surface of that tank as a heating mat,” List said. “That room stays substantially warmer than the balance of our house. It seems to be decent to keep the seeds at a comfortable temperature to get them going. Seed starting mats are wonderful if you’ve got a little bit of financial resources and space to set them up [but] just a very warm spot in your house works well.” 

List also recommended paying careful attention to the soil moisture for hot pepper seedlings. 

“We have in the past covered those with plastic and if the soil isn’t allowed to breathe, you can develop a significant layer of mold on top of the soil before the seeds get the opportunity to germinate,” List said. “[Now] we tend to keep our trays open and just leave them wet. As soon as they pop up, we immediately transfer them out into our vertical growing stands with lights.”

Use season extenders

Once your hot pepper seedlings are outside in your garden, season extenders like hoop houses will help hot peppers to thrive in the unpredictable Maine climate.

“We need to extend the season just as long as possible to get a reasonable yield out of what we’re doing,” List said. “It doesn’t have to be a heated structure, but it does have to be a hoop house kind of a structure. Without those, we couldn’t do it.”

List said that he transplants hot peppers under his high tunnels outdoors the first week of June to avoid any possibility of frost for the cold-sensitive plant. 

“It’s very late,” List said. “If we were to provide heat in that high tunnel and make it a greenhouse, we could get them out there sooner [but] the hoop house gets hot and they seem to love it. We have an irrigation system on the surface of the soil, underneath the base of the plant we use a tremendous amount of straw out there as weed suppression and to help us manage moisture at the root zone for those plants.”

However, managing moisture in the hoop house can be a challenge.

“We do have ventilation end to end, and there’s some time managing an appropriate temperature in there and maintaining a temperature in there,” List said.

Mulching is another great way to warm the soil while retaining heat. List said that the hoop house and straw mulch combination works well for his hot peppers. He added that if he were to grow hot peppers outside without a hoop house, he would probably use a heat absorbing paper mulch or black plastic mulch to retain even more heat.

In general, you can use the warming property of black equipment in order to provide the perfect conditions for hot peppers.

“Hot peppers will grow beautifully if they have warm“feet and are protected from wind,” LeBlanc said. “If you are growing in pots, black ones in full sun are great. If you are growing directly in the ground, then black plastic or a layer of flat rocks around each plant will help provide warmth.”

Watch out for hot pepper issues

While List said that most hot peppers seem to be resistant to pests in Maine, blossom end rot can be an issue.

“Regular water management and heavy straw mulch works well to help mitigate this challenge assuming sufficient calcium is available in the soil,” List said.

LeBlanc added that hot peppers are sensitive to nitrogen in the soil.

“With too much fertility they will grow beautiful plants and shrubs and not feel the need to blossom and fruit,” LeBlanc said. “Now that we know a lot more we are careful not to over fertilize.”