Digging Into Square-Foot Gardening

Now booking: Just a few summer consult spots left

“Permanent and prominent” Square-Foot Gardening grids. (Pepin M. via Unsplash)

Hi, guys!

I’ve received several emails from readers who say they’re disappointed they can’t grow vegetables because they don’t have enough property or can’t fit a large enough raised bed to make it worth the effort. But you really don’t need a quarter acre of land to have a substantial harvest.

In the late 1970s, a retired engineer named Mel Bartholomew developed a gardening method he called “square-foot gardening,” which organizes plants into 1-foot squares in raised beds as small as 4 feet by 4 feet.

Not only does his method save space, but it also saves time and strain on your back.

Bartholomew published the million-selling “Square Foot Gardening” book (and several sequels) and hosted PBS (and other network) shows that brought his method to the masses in the 1980s. Perhaps it’s time to revisit the basics for a new generation as well as those who missed it back then.

Bartholomew promoted planting in raised boxes placed on top of existing soil rather than digging into it. This was before raised beds became popular.

His technique involves filling the box, typically 4 feet by 4 feet in size and just 6 inches deep, with one-third each peat moss, vermiculite and compost (no soil). Then, instead of planting in rows, the space is divided into 16 one-foot-by-one-foot squares, each dedicated to a different crop, by placing a grid over the soil (you can make a grid or purchase a pre-made one).

He contended that if cared for properly, plants grown in this manner wouldn’t need fertilizer (the compost takes care of that, it’s true). And the elevated height of plants makes them easier to reach and cuts down on bending and stooping (also true).

Squares are designated based on how much room a mature plant actually needs. One square gets 16 radishes, for instance. Another gets four lettuce plants. Larger crops like tomatoes and broccoli get a whole square to themselves.

The dense planting method naturally shades out weeds, and the defined layout makes succession planting easy (you can follow your peas with peppers, for instance, in the square they vacate).

Some tips:

• Don’t skip the grid. It’s not just decorative—it defines your planting and keeps the system square. You can buy one or make it yourself with string, bamboo stakes, old mini blinds — whatever you have on hand (although when Bartholomew published The All-New Square-Foot Gardening edition, he strongly recommended using more “prominent and permanent” grids, like the one in the photo above. It’s probably for the best since the others will likely shift.

• Make sure your bed is no wider than four feet so you can reach the center from all sides.

• Instead of bushy varieties that take up a lot of real estate by growing outward, focus on plants that can be trained to grow vertically on trellises, like squash, cucumbers, indeterminate tomatoes and pole beans. Plant trellised crops on the west side of the bed, where they won’t shade out lower-growing ones planted to the east.

• Check seed packs or plant tags for the recommended space requirements for each plant and go with the minimum within the specified range. If the recommendation is to space plants 12-18 inches apart, go with 12 inches. Just don’t push the limits beyond that because overcrowding plants will make them susceptible to mold and fungal diseases and make weeding and harvesting difficult.

• Choose varieties with different maturity rates. For instance, there are early-, mid- and late-season varieties of tomatoes, cabbage, corn, peas, peppers and eggplants. Plant one of each to extend your harvest.

• Plant lettuce, beans, radishes and onions at 2-week intervals so that when one is harvested, another is on its way to maturing.

If you follow the Square-Foot Gardening method, let me know how it’s going (and send pictures!)

A Note for My Weekly Dirt Readers

I have just a few consultation spots left for this summer, and I wanted to offer them to you first — my most dedicated readers.

Here’s how it works:

If you’re in Nassau or western Suffolk counties in New York, I’ll come to your garden to personally evaluate one section, bed or border. I’ll test your soil’s pH, recommend plants that will thrive in your conditions, help you troubleshoot any issues and answer all your questions. After our visit, I’ll follow up with written recommendations tailored to your space.

If you’re outside my travel area, no worries — I also offer virtual consultations. I’ll guide you through collecting a soil sample to mail me for testing, and we’ll meet via Zoom or FaceTime to “walk through” your garden together.

Consultations are $250 and booked on a first-come, first-served basis. If this sounds like something you’d find helpful, send me a description of your needs and your location. I’d love to work with you.

📬 Ask Jessica

DEAR JESSICA: To my happy surprise, this geranium’s leaves are variegated! It was one of a cell pack of four. The other three geraniums have solid green leaves. How do I collect seeds from the variegated geranium to save for next year, if possible? Thank you for your help and for a fun and informative newsletter. —Karen Bartolotto

DEAR KAREN: Geranium foliage can show variegation due to deliberate hybridization, a genetic mutation or a virus. I’m ruling out a virus because the plant looks very healthy, and viral foliage mottling doesn’t typically look like the leaves on your plant.

I’m leaning toward hybridization.

Hybrid plants are created when the pollen from one plant pollinates another, either naturally (by wind or insect) or deliberately (by a breeder). Sometimes, a plant will “revert” to one of its parents and display its (unintended) qualities.

If that’s what’s going on here — one of your plants “parents” had yellow or variegated foliage, and those genes turned out to be more dominant than those of the other parent.

If that’s not what’s going on here, it’s probably that plants in the cell pack got mixed up at the nursery. In that case, the yellow one is also likely to be a hybrid.

If you were to plant seeds from a hybrid plant, its offspring would not be “true” to its parent. Instead, it would resemble one of its grandparents, which, in this case, may have been a yellow-leaved geranium or whatever the other grandparent contributed to the gene pool.

you’ve got nothing to lose, so give it a try (and report back next year!) Here’s how:

After the flowers fade, monitor the plants daily to observe the pods as they mature. Pick or cut them off when they appear dry but before they burst open on their own.

Set the pods in a dry spot for a few days or a week to continue drying, then remove the seeds and place them in a paper envelope. Place the envelope in a sealed glass jar and place the jar in a cool, dark spot.

Start the seeds indoors next winter, about 3 months before planting time in your region.

Good luck!

Got a gardening question? Ask it here.

👏 Sunday shoutout

(Alan Quackenbush)

Alan Quackenbush of Sayville, New York, sent in this cheerful photo of his blooming azalea, which he says is the last to bloom in his garden. “I wish they lasted longer,” he laments.

Until next year, Alan!

Send in your photo, and you could be featured next (bonus points if you’re in the picture!)

💡 If you do one thing this week…

Fertilize your houseplants at half-strength (and continue doing so with every other watering through fall). They’re officially in their active growing phase.

📰This week in my Associated Press gardening column

I write a weekly gardening column for the AP, so you might have seen my byline in your local paper (or news website) — wherever in the world you happen to be. In case you miss it, I’ll post the most recent here every week.

THIS WEEK: Weeds aren’t just nuisances, they’re messengers. Here’s what they can tell you

LAST WEEK: Want to grow your own rice? A step-by-step guide for adventurous gardeners

BEFORE THAT: The effect of loud outdoor noises on wildlife is worse than you might think; here’s what you can do to help

ONE MORE: Everything you need to know about the Chelsea Chop

You can read all my AP gardening columns here.

📚📺🎵 Random things I enjoyed this week

🦞 I spent a couple of days with a childhood friend at her Hamptons condo this week. It was too cold for the beach, but we played Mad Libs, watched a music documentary, made terrible coffee because we couldn’t figure out the pot and gorged ourselves at an all-you-can-eat lobster dinner. In case you’re curious, I put away two 1 1/4-pound lobsters (we won’t mention the overflowing plate of appetizers or dessert).

🎭 I saw The Picture of Dorian Gray on Broadway with my daughter Julia (my birthday gift to her), and it absolutely blew us away. I knew it was a one-woman show, but I had no idea that Sarah Snook played 26 characters! The acting was better than any I’ve ever seen — she so deserved the Best Actress Tony award she won earlier this month. And the way the show incorporated technology was breathtaking (and not cheesy at all). It was like nothing I’d ever seen.

🎥 I saw Sinners, which reminded me of From Dusk ‘til Dawn (if it had been set in Mississippi in 1932 and featured a mostly Black cast). Michael B. Jordan was fantastic playing twin brothers who return to their hometown to open a juke joint after working for Chicago gangsters. The film also features Omar Benson Miller, Hailee Steinfeld, Wunmi Mosaku and blues pioneer Buddy Guy(!). It’s part horror, part social commentary, part historical drama — and the music is fantastic! Plus there are vampires.

📺 For once, there isn’t anything new streaming over here. I’m still working on Stick and the latest season of Ginny & Georgia.

Let’s be friends! Follow me:

• @JesDamiano on Instagram

• @jessicadamiano on Facebook

• @jesdamiano on Threads

📧 How’m I doing?

I welcome your comments and suggestions, so please send them along — as well as any topics you’d like to see covered and questions you’d like answered in the Ask Jessica section.

Until next week, stay safe. Be well. And always keep your mind in the dirt. —Jessica