Carefully planning a vegetable garden makes everything that unfolds throughout the season much smoother and more rewarding. Planning will avert many problems, maximize yield, and minimize effort down the road. A lot of folks just jump in and learn as they go (and that's fine too), but planning lets us envision exactly what we want to create, which then gives us an easy blueprint to follow, step by step. Many of us have more time on our hands this year, so we can plan our best garden ever.
You've probably been planning a vegetable garden in your head for awhile now, and have probably decided already whether your garden will be in the ground or in a raised bed. There are advantages and disadvantages to each, so if you haven't made up your mind yet I encourage you to read about the Pros & Cons of each method so you get the end result that's most important to you.
You also need to decide where your garden will go. Choose a site that gets an absolute minimum of 8 hours of full sun per day, preferably more than 12.
If you're going to build a raised bed, do that next. You can find help on the Raised Bed Gallery and Build a Raised Bed pages.
Even if you will be buying starts from Home Depot or a nursery, I encourage you to do this anyway. Seed catalogs help you learn about the plants you're going to grow, and give you vital information about how much space your chosen plants will need when you start planning your layout.
One of the biggest mistakes beginning (and experienced... yeah me) gardeners make when planning a vegetable garden is planting things too close together. ("But they're so tiny! They can't take that much space!".) Oh, but they DO, and they WILL.
After you get done putting a sticky note on everything you want to grow in the seed catalog, go back and rein it in.
Don't buy seeds before you plan your layout on paper, or you'll most likely have more things to grow than you have space to grow them. The article Starting a Vegetable Garden can help.
I use a lot of Botanical Interests Seeds… yes, I am an affiliate of theirs... but their seeds are excellent and their company supports the fabulous, now dwindling art of botanical illustration. (You can download their beautiful free coloring books here!)
Considering what happened last year (Spring 2020), I would also encourage you to buy seeds early.
Draw out your garden on a piece of graph paper, laying out the beds and paths. (Okaay... you can do it on your computer.... sigh...)
I suggest making beds that are no wider than twice your reach, so that you can reach the middle from either side. Here is a hard rule: Never walk on your beds. It will compact them and cause damage to your soil ecology. Make sure the paths between are wide enough to get a cart or wheelbarrow through.
After you know what plants you're going to grow and how much space each one needs, use a circle template (or just your eye) to draw circles where the individual plants will go, giving each enough space to reach maturity without bumping into its neighbor.
If you use an app for planning a vegetable garden you will learn how to use a cool, time-saving app, but you won't learn about the actual needs of your plants. Learning about your plants, how big they'll grow, whether they'll tolerate some shade, etc., helps you to develop a relationship with them. Gardening is a relationship with living things, a mutually-nurturing partnership. For now you'll have to take my word for it, but it's in this relationship that the deepest rewards of gardening lie.
A really critical part of planning a vegetable garden is getting the timing right. If you live where it freezes in the winter, everything will revolve around your average last frost date, which if you're in the US can be found on your State University Extension Service website. This is crucial to know not only because you don't want your seedlings to freeze, but because you want them to develop the largest root systems possible so they can gather the most nutrients and water possible. Planting too early, or into cold soil, or allowing seedlings to become rootbound all will delay harvest, lower yield and nutrition, and limit quality.
When to Start Seeds Indoors covers not only when to start seeds, but when to transplant them out. If you're planning on growing your own transplants indoors, How to Start Seeds Indoors covers trays, lights, soil, and soil blocks. If you are buying transplants from a nursery or big box store, don't buy them until it is time to transplant them out. Pick out the smaller ones that aren't rootbound in their pots, rather than the larger ones that are.
And if you are planting seeds directly into your garden beds when the soil has warmed, just follow the instructions on your seed packet.
Take some stakes or stout sticks, some strong string (and whatever-else-you-can-think-of-that-starts-with "st") and step stridently out into the garden to mark out where your beds and paths will go. Oh yeah… you'll need a measuring tape, too.
Drive stakes in adjacent corners of one long side of your bed, tie a string between them, and do this over and over across the width of your garden: bed - path - bed - path...
If you're planning a vegetable garden in raised beds that are already in place, skip this step. If you're installing raised beds, make sure they get full sun and leave wheelbarrow room between them. And remember, don't build them wider than twice your comfortable reach.
And now, drumroll please:
Planning a vegetable garden nears completion when you prepare your soil for planting. If you're using raised beds, read through the Soil for Raised Beds article. You can't use topsoil in a raised bed because it is will compact down into an airless mass that will choke your plants. If you just want to buy soil, I recommend looking for a bagged potting mix that is OMRI approved, as it won't contain the toxic ingredients that common mixes may have. You will need about 32 cu ft of potting mix to fill a 4' wide x 8' long x 1' deep raised bed. The Soil for Raised Beds article has a lot more detail.
If you're gardening in the ground, and this is your first year, preparing your soil is the hardest part, the part that most people dread and often try to get around. Here was born the evil of the rototiller. Preparing your soil without damaging it is the most important part of planning a vegetable garden.
I recommend watering your garden-to-be very deeply a couple of days before you start. You want the ground about as wet as a wrung-out sponge when you start digging. It should not be so wet that it clumps together, or you can cause serious damage to the soil structure.
You will need a good strong spading fork and enough compost to spread evenly about ½" deep over your entire garden. Also buy a good complete organic fertilizer (like Happy Frog) and apply it to the surface at the recommended rate listed on the bag. Loosen the bed with your spading fork, one forkful at a time, pulling out the weeds and incorporating the compost and fertilizer as you go.
If you chop up the pulled weeds and lay them down on the surface of the soil that you just worked, they will die and eventually turn to mulch. I don't recommend doing this with grasses, though, because they have a disturbing way of reincarnating.
This is the final, but never-finished step in planning a vegetable garden, because there is always more to learn. There are many great books out there and a lot of information on this site about the importance of healthy soil to a healthy garden, and in turn to human and animal health. We need to reclaim our soils and our health, and ebooks on these topic by yours truly will be coming along this summer. Stay tuned... and may your garden fulfill your dreams for it.