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How to cultivate success by starting your plants indoors

Ask the Gardener offers tips on lighting, the proper soil mix, and watering

Reusing seed trays, or even old takeout containers, is better for the environment.Adobe Stock/La Huertina De Toni - stock.adobe.com

As of late, my dreams have been filled with fresh green sprouts and visions of verdancy. Few things excite me more about the impending growing season than planning my vegetable and cut-flower garden. Whether I am growing tried-and-true favorites or trying out a new variety of tomato, hot pepper, or annual flowers, the beginning of February marks the time to start organizing. Growing your own vegetables brings tremendous satisfaction; the produce could not be fresher than just picked from your garden, and you know precisely how that zucchini was treated before it landed on your plate. I encourage vegetable growers to include annual cut flowers alongside their victuals because the flowers draw in pollinators and beneficial insects and provide you with a steady source of bouquets to brighten the kitchen table.

Why start vegetable seeds indoors before spring? While I love the seasons in New England, our winters make it hard for warm-season crops like eggplants, hot peppers, okra, and watermelons to receive enough heat to flower. Even tomatoes that consistently fruit well in our climate will perform better and yield sooner if you start with a bigger plant, already in bloom, once we pass our frost date in mid- to late May. Other crops like cauliflower, broccoli, lettuce, and cabbage prefer cooler conditions and can be planted in early April, as long as you are prepared to cover them at night during late frosts. Lastly, vegetables like arugula, carrots, peas, mustard greens, spinach, Swiss chard, turnips, and radishes and herbs like dill and parsley can be directly seeded into the garden as early as mid-March.

Here are the things to consider when starting seeds indoors during late winter and early spring.

  • Trickery To coax the seeds into life, you must trick them into thinking it’s warmer and sunnier than it is. The first step for success is to provide bottom warmth via a heat mat. By warming the soil, the seeds respond with quicker and better germination than if they grow in ambient temperature conditions. Johnny’s Selected Seeds is an excellent choice for many seed-starting supplies, especially heat mats and temperature controllers, which are on sale. The pots you use are less important if they have been well-cleaned beforehand. Reusing old trays and six-packs is environmentally friendly and keeps them out of the waste stream. I have even seen enterprising gardeners reuse take-out containers to start seeds! Most seed packets should have information on the package telling you how many days to maturity you can expect, which helps with the timing of seed sowing. I find making a calendar aids in knowing when to start which seeds. Seed packets for warm-season crops, especially those from Johnny’s, will tell you the optimum temperature range for the soil.
  • Lighting Depending on the scale of your production, there are many options to consider. At the smaller end, affordable full-spectrum LED grow lights are available as a gooseneck with a stand or as a strip. If you have a big vegetable garden, you can graduate to grow racks with one tier of lights to as many as four or five, the price of which rises with each tier added. Be sure to purchase a timer for your lights as well. Vegetable and cut flower seeds will require 12-16 hours of light daily for the best results. The Spruce has tested and reviewed many lighting options and provides recommendations for nearly every type of gardener, from the newbie to the seasoned professional.
  • Soil Buy a germination mix, which most garden centers carry. If you need only a small amount, consider splitting a bag with a fellow gardener or simply storing it for use next year. The germination mix is designed to encourage easy seed rooting, hold moisture, and be well-drained. It seems like a paradox that soil should hold moisture yet be well-drained, but the germination mix achieves this delicate balance.

Here are some things to watch out for once you sow your seeds:

  • Watering This is very important, especially if you are providing bottom heat, as the pots will dry out faster than you think. Before you sow seeds, thoroughly wet the soil so that the water drains from the bottom of your pot. Consult the seed packet or seed website for information on sowing depth. Some seeds are sown on the soil surface because they need light to germinate; others want to be lightly covered, the cue to break dormancy being soil temperature. Regardless of sowing depth, the seeds are initially in a precarious position. Imagine trying to fill a shot glass with a fire hose. Now imagine trying to fill that same glass with a gentle rain. Watering seeds and seedlings, mainly when germinating, must be done carefully to avoid drowning or knocking them over. Use a watering can with a breaker or rose so that the water rains down softly.
  • Lighting Your source should be close to the soil surface to start, and as the plants grow, adjusted to avoid burning the leaves but still be bright enough to encourage growth. If your seedlings are stretching or look spindly or thin, they are not getting enough light.

Despite the many steps outlined here, growing your own vegetables can be easy and rewarding. And as gardeners will attest, making mistakes is part of the evolution of becoming a better gardener. Plants are resilient, as are people, and there is great comfort in the rebirth of spring, especially if coaxed a few weeks early indoors.

Uli Lorimer is the director of horticulture at the Native Plant Trust in Framingham. Send your gardening questions, along with your name/initials and hometown, to ulorimer@nativeplanttrust.org for possible publication. Some questions are edited for clarity. Subscribe to the Globe’s free real estate newsletter at Boston.com/address-newsletter.

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Correction: Due to a reporting error, previous versions of this story gave an incorrect name for Johnny’s Selected Seeds. The Globe regrets the error.