Why Grow Tomatoes in Containers?

This is the first year that I am growing the majority of my tomatoes in containers, and wow, are they doing well! I decided to go with containers because I’m using my raised beds for a cutting garden, and I’ve found that growing tomatoes in my regular garden beds results in slow growth and late-season diseases. I planted one tomato in the ground and it is definitely lagging behind the guys in the containers.

Why grow tomatoes in containers? A few reasons:

An 18-inch container may be a little tight, but most tomatoes do well in 18- to 24-inch containers.

1. You control the soil. For my container tomatoes, I used large containers and a high-quality potting mix.  The mix has most of what the tomatoes need in terms of nutrients and I will add some bone meal or liquid fish emulsion as the tomatoes produce fruit to keep the calcium and fertility levels up.  The potting soil also lacks all the soil-borne diseases that tend to hang out in the ground—that’s a good thing!

2. Decent drainage. We’ve had a pretty wet early summer in Minnesota. (We had a solid 3 inches in the past week and many areas of Minnesota had much more.) Unlike the ground, which can get water-logged, containers drain well. (I’m considering adding pot feet to my containers to ensure even better drainage.) They have holes in the bottom so excess moisture moves away from the roots, preventing root rot. One disadvantage of container tomatoes is that in dry spells you have to stay on top of watering. Tomatoes need consistent—but not excessive—moisture throughout the growing season to perform best and avoid blossom end rot.

3. Air circulation, easily. Every time I plant tomatoes in the ground, I end up putting them too close together. They look so little when they go in the garden and it’s hard to imagine how big they will get — and how entwined in each other.  With tomatoes in pots, I can move the pots if they get bigger than expected and start encroaching on their neighbors. Air circulation is another important factor in the health of tomatoes.

4. Easy to cage. The pots I chose for my tomatoes are all 18 inches in diameter. For really large tomatoes, you could go even bigger, but the 18-inch pots are a perfect fit for the standard size tomato cage, which I put on the tomatoes a few days after planting. Don’t wait to cage your tomatoes.

Green tomatoes already on some of the plants!

5) Easy to pick. Container tomatoes are elevated by the height of the pot so it’s easy to see when fruit is ripe. The elevation also makes it harder for rabbits and voles (though unfortunately, not squirrels) to get at the tomatoes. For squirrels — a bit more engineering may be necessary.

Many of the usual instructions for growing tomatoes apply to container tomatoes — place them in a very sunny spot, plant them deeply in the container to allow roots to form, and pinch extraneous foliage to keep the plant focused on producing fruit. Generally, determinate tomatoes are recommended for container growing, though I’m growing several types of heirloom tomatoes and I think most of them are indeterminate.

I will report how things go as the season progresses! Do you grow tomatoes in containers?



How to Build a Vegetable Garden Box for Your Deck

My sister and her husband have a large, sunny backyard, but they prefer to leave that space open for pickup football games and other neighborhood fun. (They have four children of their own and lots of little visitors.) So, when they decided they wanted to grow some vegetables, the solution was to build a deck-side garden.

My brother-in-law, John, is an engineer, so he had no problem coming up with a good-looking, efficient design. It’s also easy enough to construct that you don’t have to be an engineer to build one. So, here’s John’s Deck Garden — and thanks to my sister, Elly, for sharing the photos. (By the way, these are larger photo files, so feel free to click on the thumbnails to get a closer look at what’s happening.)

John and Elly wanted a garden large enough to grow a couple of tomatoes, some basil and a few other herbs, so they decided to build a box 6 feet long by 2 feet wide. After buying 1-by-8 cedar boards for the sides, some 2-by-2 lumber for the support pieces and a piece of plywood for the bottom, John (with assistance from my dad) went to work. He cut the lumber to size, then used wood glue to attach the boards on top of the plywood bottom (above).  He then attached the supports inside the box (below) He started building the box, attaching the side pieces to the supports using deck screws. (This is where having two people working makes the job much easier.) He built it one layer at a time, so that the final box is about 22 inches deep.

adding support to deck box
Once the bottom was attached to the first row of boards, an internal support was added.

Once the box was complete, John flipped it over and attached four strips of 2-by-2 to the bottom to raise the deck garden off of the deck. It’s not shown in the photo, but he also drilled some drainage holes in the bottom and lined the box with landscape fabric. The fabric helps the bed retain some moisture and the holes make sure it doesn’t retain too much.

man's foot in garden box
John’s 6-foot-5, so the box is plenty deep!
garden box flipped over
The 1-by-2s helped keep the box off the deck to prevent rotting.

With the box ready, John and Elly filled it with a mixture of top soil and compost and planted their tomato and herb starts. The photo at right was taken right after planting, and I’ve since heard that the plants are all doing well and the tomatoes have gotten big and already have blossoms. What a great way to raise vegetables in a small space!

small plants in deck garden
With soil added, herbs and tomatoes where planted in the box.