Welcome back to our “Year in the Organic Garden Series!” In February, we focused on techniques for successful seed starting. If you missed the post, or want to refresh your memory, please take a look at February in the Organic Garden.
Now that we’re caught up, we turn our attention to the official start of the outdoor organic gardening season. March is prime for cool season crops which means we’ve got a lot of leafy greens, brassicas and root crops to sow and grow. We’ll get to that in a moment, but first a Public Service Announcement:
You will likely start to see tomato and pepper starts in big box nurseries any day now.. These popular garden edibles are tropical in nature and really shouldn’t be exposed to temperatures less than 50 degrees Fahrenheit. Planted too early, they will either die or be stunted. Be kind to your tomatoes and peppers by waiting until overnight lows are above the 50F threshold (May…usually) and you’ll have much better luck. It’s always easier to grow with the seasons than against them!…And now we return to our regularly scheduled programming.
March weather can be tricky, so keep an eye on the forecast for best success. We will hit the highlights of this month’s activities below.
Radish, Carrot, Beet, Spinach, Lettuce & More can all be planted from seed in March. If the ground is frozen early in the month, check back in a week or two and hopefully it is workable. Directions for seed spacing and depth are always on seed packages or easily looked up online. Be sure to label what you planted and where. All the seeds look the same when covered with soil!
Best yields come from planting more seeds than mature plants you’ll need. Once the seeds germinate, thin the weakest looking sprouts from your garden to leave only the strongest to mature. We recommend succession planting, which is just a fancy way of saying sow only part of the area you want to use for any given plant and then come back and add more seeds at 2 week intervals to fill your space. This will give you a more steady harvest over a longer period of time. Of course, you can plant all of your seeds at once to get a single, bigger harvest.
Your seedlings won’t need fertilization until the second set of leaves appear. Until that time, the seed itself is providing all the nutrition it needs. Assuming you’ve got compost and other nutrient sources in your soil, the need to add additional nutrition in March is minimal. We’ll talk more about fertilization in April.
If your seeds don’t germinate, or take forever to do so, it’s likely that conditions just weren’t right for any number of reasons. If this happens, they may yet sprout as the soil warms. That said, it may be best to sow another round to get better results. Each year is different due to weather patterns. Building flexibility into your mindset and approach will pay off as the season progresses.
If your Seed Potatoes have eyes, they’re ready to plant. You can plant them either whole (if smallish) or cut into pieces if larger. The key is to have at least 2-3 eyes per piece or potato you plant. More eyes yield more, smaller potatoes due to competition. Less eyes produce less, larger potatoes for the opposite reasons. Whichever way you choose to go, you should have success. If you do decide to plant pieces, give them a couple of days after you cut them to form a “skin” and you will have better results. Potatoes should be planted 6-8” deep and are heavy feeders. Go ahead and mix a balanced organic fertilizer into the soil as well. As the potato shoots grow, you can cover the bottom half with soil to produce additional tubers. Just be sure to always leave enough leaves to collect sunshine!
Cool Season Starts
Broccoli, Kale, Cabbage, Collards, Brussels Sprouts, Mustard Greens & Cauliflower starts can all be planted in the garden this month. If you buy your starts from a garden center, they should be ready to go into the ground.
If your starts are from seeds that you started last month, you’ll need to prepare them for outdoor conditions before you put them in the ground. This process is simple and can’t be rushed. It takes about 10 days to properly “harden off” your starts. On Day 1, take them outside for an hour or two and then bring them back inside. Gradually increase the amount of time you leave them outside until they are able to spend 24+ hours outside and still look great. Then, and only then, they’re ready to go into the ground. Hardening-off your starts allows
them to get used to temperature changes, wind, sun, rain, etc. If a below freezing cold snap is predicted, best to hold off until it has passed to go for a full 24 hours outside or to plant your starts.Rushing the process is a recipe for disaster. Take your time and take your cues from your starts. They’ll let you know when they’re ready! Once planted, young starts will need to be protected from cold snaps with row covers or by other means.
Rhubarb, Asparagus, Fruit Trees, Berry Bushes, Grapes and more can all be planted now. If blueberries are in your plan, you’ll likely need to add sulfur to the soil to achieve the highly acidic soil conditions that they prefer.
It would take books and books to give instructions on how to plant and grow everything that you can in March. Don’t be afraid to ask for specific help depending upon what you’re planting!
Seeds to Start
Now is the time to start your warm season crops from seed. The steps are the same as for cool season crops and were covered in the February post. March is great for starting Tomatoes, Eggplants, Peppers, Parsley, Dill, Basil and more!
Looking Forward to April!
In April, we will cover the progress of your cool season crops and getting ready for the warm season.
Thank you for taking the time to read through this guide. We welcome your comments and questions. Happy organic gardening!
Where can I find the “and more” list for direct sowing in March?
Peter Lucey says
Nice concise advice.
Thanks for your question. The “and more” list for March Direct sowing is a little longer than we have room for here! For edibles, leafy greens such as Kale and Swiss Chard would also be in this group. Turnips too. We should have mentioned in the article that seed packs for edibles and flowers have sowing timing recommendations on the back too. When seed shopping it’s always a good idea to lay out the packets you’re interested in to make sure that the sowing dates work with your garden plan!