By Denise Keniston

John Hallam and Terri Swartzel consider themselves amateurs on Somerville’s flourishing home gardening scene. They relish the challenge of growing crisp, colorful vegetables and bright, bouncy flowers in an urban environment set against the backdrop of New England’s often inhospitable growing conditions.

Ten years of trial and error and they’ve learned a few things first: a great garden starts with good water. Last year, they installed an underground, low-tech rainwater harvesting system that holds 2000 gallons of water collected from two roof gutters, enough water for their backyard garden.

Trevor Smith, President of Land Escapes Design, designed the system. “The rainwater comes from the downspouts and into a catch basin with [what looks like] big milk crates that filter out large debris like leaves and twigs,” he says. “There’s a mesh bag on the inside which filters out fine debris, such as dust and grit and pollen and flows into the cistern holding 2000 gallons of cleaned rainwater. The pump draws up the water for garden irrigation.”

John and Teri planted dozens of seedlings in their cellar back in January and February. They purchased the best seeds possible and, using containers like recycled food and drink containers, boxes, and jars, put seeds in the soil and watched them grow.

After the starters grew to an inch or more Teri and John carried them out to the raised beds and under Teri’s makeshift cold frames. “Getting a jump on things is important because the New England growing season is short and you extend your growing season with starters,” says Teri. “This year we brought some starters out to the raised bed area and had to bring them back in at night because the temperatures starting dropping a lot. We had to wait to put them in the ground.”

Makeshift cold frames are the intermediary step between starters and direct planting. John uses salvaged pieces of wood for a box and then covers it with plastic to capture heat and diffuse direct sunlight. They are situated on the corners of the raised beds where eventually the starters will be planted directly into the ground. “Cold frames are the gardener’s best friend! If you don’t want to splash out lots of money buying one,” says John. “Ours isn’t expensive or elaborate but they get the job done, which is a place to transition your starters before putting them in the ground.”

Teri and John have a mixture of vegetables, flowers, and trees. Their raised beds are seeded with beans, peas, lettuce, tomatoes and more. A makeshift cold frame is a starter for seedlings nearly ready to be planted directly into the ground. “We have four raised beds this year for our vegetable garden. Every year we rotate crops to maintain the health of the soil,” says John, “You also keep track from year to year what works well and what doesn’t and then you try new things. For example, plant vegetables that grow well together, like tomatoes and basil. Perfect!”

For beginners, John and Teri have a list of “no fail” vegetable plants that will get you started your first couple of years. “Tomatoes, asparagus, peas, beans, and peppers are fairly easy to grow,” says Teri. “Although tomatoes and peas need fertilizer and good soil and water.”

John is British and as such has a passion for roses. But, they can be finicky and difficult to grown. “We had a severe winter a couple of years ago and many of my roses never recovered,” says John. “I’ve had to prune back several of them in hopes they will bounce back. I’ll just have to wait and see.”

John and Teri are members of the Somerville Gardening Club where they get much of their information and information. The SGC meets the second Wednesday of every month. They can be reached at Somerville Garden Club, P.O. Box 441895 W. Somerville, MA 02144 or membership@somervillegardenclub.org.