With rising food prices, there is increased interest in growing vegetables at home.
Homegrown New Hampshire host Emma Erler, lead horticulturist with Kirkwood Gardens, has recommendations for the essential elements needed to set up a garden for a plentiful harvest.
Sun
“You really need to pay attention to how much sunlight your garden gets every day,” she says. The majority of vegetable crops all need at least six hours of direct sunlight a day.
Plants that don't fruit, like lettuces, spinach, and herbs, are happiest in that six hour window, and can tolerate slightly less.
But if you're hoping for that beautiful tomato, eggplant or pepper, you need 8 or 10 hours of direct sun a day.
Erler recommends gauging exactly how much light is hitting your garden before getting too excited about what you're going to grow. You can simply observe the sunlight each hour throughout the day or find sun-tracking apps online.
Temperature
Home gardening crops fall into two categories; either cool season crops or warm season crops.
Cool-season crops are ones that prefer to grow when temperatures are still cool; this includes lettuce, peas, broccoli, cabbage, kale, spinach and radishes.
They tend to grow poorly in the heat of summer and in some cases will bolt in the heat, which means they will flower, get very bitter and stop producing.
Erler says you can sow the seeds of cool-season vegetables as soon as you can start working the soil in spring, when soil temperatures are between 40 to 50 degrees. They can tolerate a frost, and can be planted again in fall once temperatures cool down again.
Once the risk of a frost is past, it’s time for warm-season crops: tomatoes, peppers, eggplants, melons, cucumbers, and squash.
None of these can tolerate frost at all, so you need to wait to plant these until after the risk is gone. Soil temperatures need to be 50 to 60 degrees to plant these crops.
Because they require a long growing season, a challenge in New England, warm-season crops will not mature if seeded directly into the garden. Warm-season crops need to be started indoors several weeks before planting time, or they can be purchased as seedlings from a local garden center.
Tender crops like cucumbers, pumpkins, squash, and melons can be seeded directly into the garden. If you choose to buy these plants as seedlings, be careful transplanting them – they don’t like their roots disturbed.
Erler recommends placing hot caps or cloches over the soil for several days prior to sowing the seeds of tender crops to warm the soil. Keep them in place until plants emerge and are growing vigorously.
Water
An inch of water per week is a good rule of thumb for vegetable gardens, ideally in the form of rain. Expect to do some irrigation.
“A good hack is just to dig into the soil 1-2 inches with a trowel or your fingers,” Erler says. “If the soil is dry and warm, it's time to water. If it feels cool and moist, you can wait.”
She recommends a rain gauge for all gardeners. There are many you can buy, or use a straight-sided can and a ruler.
And as always, Erler reminds gardeners that mulch helps to retain essential moisture in the soil.
If you have a gardening question for Homegrown NH, email or send a voice memo to HomegrownNH@NHPR.org.
See you in the garden!
Homegrown New Hampshire is a collaboration between Squam Lakes Natural Science Center and NHPR.
