Backyard vegetable gardens are healthy for people and the planet. Here's how to start yours

If you want healthy food, experts say to eat what's local, organic and in-season. Those foods benefit the planet too, because they are less taxing on the soil and they don't travel as far.

It doesn't get more local, organic and in-season than a backyard vegetable garden.

At this time of year, many backyards across the country are still covered in snow. But it's the perfect time to start planning for a garden because you'll want to have supplies ready to start planting just after the last frost date in your area.

Below are some tips on how to plan a backyard garden and reasons why you should do it.

Homegrown vegetables have fewer emissions

Vegetable gardens benefit the surrounding ecosystem by adding diverse plant life, especially where they replace grass or cover a deck or patio. They also can provide flowering plants for pollinators.

The plants capture and store carbon in the soil, promote healthy soil by preventing compaction and can make the air cooler on rooftops and patios, according to Ellen Comeau, who chairs the advisory council for the Cuyahoga County Master Gardener Volunteers with the Ohio State University Extension program.

''There's this whole idea of a zero-kilometer meal, that I don't have to travel anywhere, except my backyard, to make food. That certainly helps the climate,'' said Carol Connare, editor of The Old Farmer's Almanac.

Gardening has health benefits

The health benefits from gardening are multifaceted, ''social, emotional, nutritional, physical,'' said Katherine Alaimo, an associate professor of food science and human nutrition at Michigan State University.

Gardening promotes physical health because it requires a lot of movement. The food is typically picked at the height of ripeness and eaten fresh so it tends to have more nutrients than grocery store produce.

Alaimo said most gardeners don't use pesticides and grow their food organically. And of course, when you grow more produce, you eat more produce.

Alaimo said gardening also connects people with nature, provides a sense of responsibility and accomplishment and encourages sharing harvests with friends. All of that can contribute to reduced stress, lower blood pressure and higher energy, she said.

Picking the right spot and budgeting

Sunlight is the biggest factor in choosing where to put your garden. Most produce wants at least six hours of sunlight per day. If sunny spots are few, save them for fruiting plants because leafy greens can tolerate more shade.

It also helps to have a nearby water source because you'll get more food for less effort if you're not lugging buckets of water a long way.

If you're growing in the ground, Comeau said to start with a soil test to determine its acidity and nutrient makeup. Soil samples, once bagged or boxed, can typically be sent to a cooperative extension office at a university. The Old Farmer's Almanac offers a list of extension offices by state. The results will give you an idea of what to grow and whether you need fertilizer or other amendments.

After finding the right spot, Comeau said the next step is figuring out how much you have to spend. That determines how big the garden is, whether you sow seeds or buy baby plants known as starts and how many supplies you can afford.

Another major investment: fencing for pests. That means digging fences into the soil to stop burrowing animals like groundhogs, making them tall to deter deer or installing netting for climbing critters.

Choosing what to grow and when to start

What you can grow depends on what falls into your region's plant hardiness zone. Californians can grow olives more easily than Ohioans, for example.

Connare recommends finding out what plants are working for your neighbors.

Once you've narrowed down what can grow, pick what appeals to you. Kevin Espiritu, founder of Epic Gardening, said he used to advise people to focus on what grows the fastest and easiest, but now he also emphasizes choosing what you like to eat.

Connare also recommends adding flowers to attract pollinators. Local garden centers are good sources of knowledge about what native plants will attract beneficial insects.

Espiritu said to figure out the last frost date in your area and plan around that. Many fruits and vegetables are best planted after the frost threat has passed, but some can go in earlier. Cool-season crops like leafy vegetables can tolerate slightly colder temperatures. Seeds can get started indoors weeks before the last frost date.

Comeau said seed packet labels often provide instructions.

''The label will tell you when you can start it and when it can go into the ground. Some obviously go right into the ground and some can be started ahead of time,'' she said.