The weather is warmer and the fear of frost is fading. It's time to get digging.

Local gardeners mean that quite literally. The first step to building or maintaining a thriving garden is to pay attention to the soil, says gardening enthusiast Eileen East, who is also a Master Gardener with the Penn State Cooperative Extension.The dirt that we use to grow our vegetables, flowers, and lawns is so important that the United Nations and the U.N.'s Food and Agriculture Organization has declared 2015 the International Year of Soils.Prepping the ground: Know what you haveThe Penn State Cooperative Extension offers inexpensive soil testing kits to screen your garden or lawn for common nutrient deficiencies. This is a good first step for gardeners who aren't sure what type of soil they have or what changes might need to be made and should be done every three to five years. Now is the ideal time to have soil testing done, while there is still time to make changes before planting.It's also important to consider how your soil's origins can affect your garden today. You may live on a cleared lot but the soil surrounding your house was likely once forested, and the soil will reflect its heritage of growing healthy trees."There's a big difference in the structure of soil in forest areas as opposed to the prairies," said East.She noted that plants most homeowners prefer to grow, including flowers and vegetables, have deep, delicate roots that require the loose, rich soil and deep top soil of a prairie or grassland environment.Local trees and forest plants evolved to grow in our more compact clay or mountainous soil, which has a very thin layer of top soil made primarily from tree leaves and other organic materials. Tree roots spread out, not down, with strong roots. This is the reason that hearty weeds with strong tap roots, like dandelions, thrive in local soil. Unlike more delicate plants, trees also have the ability to make most of their food from photosynthesis. This is why they can survive on very limited top soil."When you try to plant prairie plants in a mountain, you're going to find shale and sandstone and clay," said East. "The plants with their nice, leggy root systems can't get into the soil."To test how deep your garden's topsoil is, take a long, thin rod and press it into the ground. The rod should slide down easily through the top soil before striking hard ground."That's all the room your more delicate plants have to grow," said East.Feeding the soilTop soil should also have a pleasant, earthy smell.Cultivating rich top soil will result in nicer plants, but it's also easier for the gardener in the long term. By keeping soil well-fed and focusing on plants' needs, you'll reduce the need for watering and weeding.In her own gardens, East prefers a more organic method of gardening. She uses wood chips and various forms of compost to feed the soil, retain moisture and keep down weeds.She noted that rich top soil should hold its shape when squeezed and not crumble apart. If dropped in a glass of water, it should remain together fairly well and absorb water.East got a jump-start on creating a healthy growing environment in her mountainous yard by building raised beds and bringing in purchased top soil. She has dedicated the past few years to maintaining that healthy top soil.Raised beds are ideal for vegetables, but flowers also need a deep, loose soil for optimal growth, she noted. Roots will tend to go sideways in more compact soil, leading to stunted growth."If you're not composting, get started now. Use what you have on hand," she said.One form of composting in East's garden is allowing wood chips to naturally decompose, both in a large wood chip pile near the garden and directly on top of the plants. (You can purchase wood chips in bulk from a tree or gardening company.) She also saves used coffee grounds to combine with mulched leaves, which she mixed together and keeps moist to accelerate decomposition.She prefers worm composting for kitchen scraps."Plants evolved with worms. They have mutuality," she said, noting that plants, the soil, and the living things in the soil must all work together to thrive. "All of this is a mutual cycle."In the garden, worms also deepen and loosen top soil by burrowing into the ground but native worms are burrowers, not efficient eaters, and won't make good composters. Stick to worms known for composting prowess such as the red wiggler.Dealing with weedsIf you're facing a garden filled with weeds, you're not alone. Take the time now to clean things up and remove weeds for a fresh start.If you're creating a new bed, you can lay down black plastic to smother the weeds and kill seeds before they germinate. Mulching existing gardens or new plantings with wood chips will have a similar preventive effect.You can also dig out individual weeds, but be careful not to disturb the soil too drastically."You don't want to churn things up too much," says East, who noted that tilling and turning over the soil can bring weed seeds to the surface and compound the problem.She also keeps a section of her garden dedicated to the native plants that were already growing in her home's wooded lot. She lets this area grow unfettered in the background of the more manicured flower garden. This could also be a good place to add flowering shrubs or trees if there is room, she added."I have a cultivated side of the garden, and my natural side," said East. "Don't get rid of the things that you love. Find a corner of your garden and let pollinators grow."A healthy garden with rich, deep top soil will naturally have fewer weeds, since most weeds have deep tap roots that thrive in compact soil, she noted. Those weeds that do grow will have less formed roots and should be easier to remove.