Planning A Spring Garden

Early spring is a great time to start planning your garden — choosing what species to plant, what use to make of the space that is available, and determine what your plants will require.

William Hastings, the University of New Hampshire Cooperative Extension’s agricultural field specialist for Coös County, said planning helps to get the most out of your garden space.

“They’re gonna want to think about things like, do my plants want full sun or shade? Should I transplant seedlings or should I direct-sow seeds? Is the plant I’m planting an annual or biannual or perennial, and how much space does this plant need when it’s mature?” Will said.

By and large, the seed catalogues and seed packages provide the necessary information about what plants are suited for New Hampshire’s climate and what the plants’ needs are.

Seeds will keep for several years if stored properly, but the Extension recommends buying only enough seeds for the current year’s use. If you buy more seeds than you need, it is a good idea to keep them in a cool, dry place. Those in laminated foil packets are likely to stay dry, but those in paper packets should be kept in tightly closed jars or containers and maintained around 40°F with low humidity, according to https://extension.unh.edu/agriculture-gardens/fruit-vegetable-crops.

The Extension warns that gardeners who save seeds from their own gardens may have seeds that are the result of random pollination by insects or other natural agents, and therefore may not produce plants like the parent plants.

Asked how a customer can be sure whether purchased seeds are viable, Will said, “By and large, seed companies are going to do their best to circulate that stock and make sure that what they’re selling is viable, but there are some tests for seed viability.

“I think without getting too into specifics, one option that folks can do is take a sample of those seeds, and they could soak them in a bowl of water for maybe an hour, and then lay them out on a moist paper towel, and make sure that towel stays moist, and over the next couple of days, they should see those seeds start to swell and crack and send out a root. As long as they do that, then, if we’re at a decent percentage of germination, then we can consider those fairly viable.”

With longer-season crops, it is a good idea to arrange an early launch of the growing season by starting the plants indoors.

“An example of that would be a tomato plant,” Will said. “If we can get a nice vigorous transplant going, that’ll help it get a jump-start on the season.

“Shorter-season, quick-growing crops like lettuce can either be started as a transplant or direct-seeded. Things with a really long root don’t like to be transplanted a lot of the time, so carrots would be an example of something that we would want to direct-seed. We wouldn’t want to try and transplant a carrot.”

Some plants, such as kale, will keep producing all season long, allowing the gardener to continue harvesting it throughout the summer and well into fall. Broccoli, on the other hand, will provide only one harvest.

“This is a reason why it’s good to read the seed packet,” Will said.

“Spring is also a good time to clean up our gardens or our planter containers,” Will continued. “We want to remove any old dead material or debris from last year, and this is important because that can harbor different pests or diseases.”

He said that means focusing on cleaning off what is on the surface, such as old tomato stems.

“Leftover roots in the soil are going to be okay the majority of the time. Those are just going to break down and contribute to your soil’s biodiversity, but tilling and hand-weeding and mulching are all good practices to keep on top of early-season weeds,” he said.

“If folks haven’t taken a soil test in several years, they may want to consider submitting one for testing,” Will noted. “You can reach out to your local Extension office and we would be happy to provide you with a sample form and guidelines. That’s going to tell you what nutrients your soil has in abundance and those that you should incorporate to provide proper plant nutrition throughout the growing season.”

It is a good idea to delay planting until the frost danger has passed, which usually means waiting until at least Memorial Day to plant the garden.

“Memorial Day is a conservative estimate of the last frost date in Central New Hampshire,” Will said. “While this winter wasn’t too impressive, late-season frost can still kill or damage newly growing plants, so it’s good to wait until this danger is past before we put out any unprotected plants.”

Preparing plants that have been grown inside from seedlings for being transplanted in the garden requires some acclimation — called “hardening” —, according to Will.

“Plants that are growing indoors in a controlled environment, especially under artificial light, are much more fragile than ones that have been grown outside,” he explained, “so we want to slowly introduce them into the real world. A good way to do this is to slowly increase their exposure to outside conditions.”

Start by placing them in a shady place on the porch for an hour or two, then bringing them back inside, he said.

“Then bring them outside, and then we’re slowly going to increase their exposure,” he continued. “So we’ll set them out for a few hours the next day, and slowly increase their exposure to the full sun, and get them used to being in the wind.”

“Most importantly,” Will said, “have fun with it and enjoy being outside.”

Those seeking more specific information can seek answers to their questions through Ask UNH Extension at 1-877-EXT-GROW (1-877-398-4769) or answers@unh.edu, a free service that connects home gardeners with Master Gardener volunteers.