Preparing Your Soil For Planting Vegetables — Portland Edible Gardens: Raised Garden Beds, Edible Landscaping, and Vegetable Garden Help in Portland, OR (2024)

It is a glorious time to live in the Willamette Valley.

It feels to me like the natural world around us has been at its absolute peak lately. The Dogwood blossoms are erupting in shocks of pink and white and Spring feels like it is finally full-on. This last stretch of sunshine has brought it all together. It feels like there is a palpable sense of sweetness, joy, and a welcome softness everywhere. A fortunate time indeed.

With all of this sun and sweetness comes, of course, the promise of a bountiful vegetable gardening season!! The soil is finally warming up, drying out, and things are ready to grow. And not just the dogwoods and the lilacs, but the seeds and the starts we sow in our home veggie gardens!

If you are finally stirring from the sleep of winter and thinking about your edible garden, this post is for you! Whether you are just starting an edible garden for the first time or tending the soil you have planted for years, before you begin, you must give your garden some love and care, preparing that soil for a long season of providing for you.

At Portland Edible Gardens we are big proponents of Raised Garden Beds, which can makegrowing vegetable much easier, starting with a high quality, fertile, weed-free soil mixture that we deliver and install, rather than improving your soil over time by adding amendments. Nonetheless, we are also big fans of the original (and in many ways more natural), in-ground gardening method, which we will discuss here.

If you are starting a garden for the first time, you have a bit more work ahead of you than your friends who have existing gardens. The first year is definitely the hardest as you are likely starting with an unimproved soil that needs a lot of work before vegetables will thrive in it!

Step 1: Choose a Sunny Location:

To oversimplify, vegetables need three things: Sun, Soil, and Water. And while poor soil can be improved, and water can be delivered to any part of your garden, shady places on your property will remain shady. Even the most skilled gardeners will not be successful growing in shaded conditions. So the first step to having a productive garden is to choose a sunny place that receives at least 6 hours of direct sunlight every day!

Step 2: Remove All Existing Vegetation:

Your vegetables will struggle if they have to compete with grass, weeds, or other plants while they grow, so it is important that your vegetable garden area is free of all vegetation at the time of planting. Remove existing vegetation (roots and all) by hand, using a sharp garden spade, or other hand tools. Send vegetation to a compost pile where it can be turned from a nuisance into a valuable amendment and plant food! Avoid planting vegetables where you have ongoing weed problems as weed seeds may persist hidden in the soil. If you are converting a lawn into an edible garden space, you may want to rent a sod-cutter to avoid the strenuous work of removing sod by hand.

Step 3: Apply 4-6” of Quality Compost on Top of Bare Soil:

Compost is truly the miracle ingredient of organic gardening. It’s benefits and contributions to your soil are too numerous and complex for this blog post, but among other things it improves drainage and moisture retention of soil, adds fertility and essential plant nutrients, increases diversity of soil biology, and improves soil structure. The importance of the quality of the compost that you add to your soil cannot be understated. Good quality home-scale compost can be excellent as long as it is completely composted, and has not been too wet (anaerobic) during decomposition. Finished compost should have a pleasant earthy smell, not a rotten or sour aroma.

Step 4: Work the Compost into the Top 12-15” of your Soil:

This is the hard part. And also the part where hard work will pay off! “Tilling” your wonder compost thoroughly into your soil will do a number of things: It will allow the compost to do its magic of integrating with your soil, it will disperse nutrients throughout, it will break up clods in your soil so plants and roots can grow more easily, and it will aerate your soil which will make plant growth happen at a much faster rate. Use a flat spade and a garden fork for this activity, and take your time making sure that clods are well broken up and compost is well integrated!

If you have a dedicated garden space that you have grown vegetables in before, the hardest work is behind you! Your job now is to maintain and replenish your garden on a seasonal basis. While you will never again have to hack away at stubborn sod or break up heavy clay with a pick axe, you do have important responsibilities in caring for and feeding the soil that feeds you.

Growing vegetables asks a lot of our gardens. Not only are we growing a diversity of plants at a high density, year after year. We are removing them from the garden and nourishing our bodies! You are what you eat, and so, in so many ways, we are the nitrogen, phosphorous, potassium, and myriad other micro-nutrients that we are taking from our generous soils. If we aren’t vigilant in replenishing those nutrients each year, our soils and our vegetables will become impoverished. The two Spring ingredients that are key to your edible garden’s health are good quality compost and organic fertilizer.

What follows is your simple guide to waking your garden from winter sleep and preparing your soil for the first successful garden plantings of the year!

Step 1: Remove Old Vegetables and/or Winter Mulch

Take the time to fully remove any vegetables that remain from last growing season. If you have covered your garden in the Fall with a straw mulch, go ahead and collect it and put it in a compost pile where it can decompose and become valuable compost. If you have vegetables that are still producing for you like Winter Kale or Leeks or Garlic, work around those plants removing everything else. In the future, plan your winter plantings so that they are all in one part of your garden so you have a nice open space to work with in the Spring.

Step 2: Add Compost and Organic Fertilizer

Compost and organic fertilizer are both very important and very different ingredients that will provide immeasurable benefit year after year. Compost contributes some nutrients to your soil, but its main value is in the contribution of organic matter. Organic matter plays many important roles in your soil including, building a nice crumbly soil structure or “tilth,” improving both drainage and moisture retention, maintaining and increasing soil biological life, preventing erosion, and making nutrients available to plant roots. Organic fertilizer, on the other hand, provides many of the raw nutrients that vegetables need to thrive.

Apply 1-3” of good quality compost and a heavy dusting of organic fertilizer (specified for vegetables) on top of your bare garden soil. The amount of compost and fertilizer needed will vary depending on the organic matter and nutrient levels of your soil. A soil test can give you detailed information about just how much you need, but in general newer gardens with heavier soils of poorer quality, or with issues of vigor need more compost and more fertilizer. Mature, healthy gardens that have been well maintained, need less.

Some excellent compost choices that are available locally:

Step 3: Work the Compost and Organic Fertilizer into the Top 8” of Soil.

My tool of choice for this activity is a garden fork which does an excellent job of tilling soil, integrating compost, and breaking up any clods. Make sure that amendments are well mixed. Finish the process with a hard rake breaking up surface clods and raking to an even surface. A fine surface texture is especially important for germination if you are going to be planting seeds in your garden bed.

As always, when working your soil it is very important that the soil is not too wet! Working wet soil can damage soil structure. It’s also just a big pain! To find out if your soil is dry enough to work, squeeze some soil into a ball in your hand. It should hold together, and when you drop it on the ground, it it breaks open it is probably dry enough to till.