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?



411 on Cracked Tomatoes

I was out of town Wednesday night and came home to three inches of rain in the rain gauge and a handful of cracked tomatoes.  The two items are related.

Why Tomatoes Crack: To grow well and fruit profusely, tomatoes need even, consistent moisture. I water tomato plants during dry periods to encourage fruiting and healthy growth. But when Mother Nature dumps a bucket of moisture on the ground, the plant naturally takes it up and the fruits crack. Their skins can’t grow fast enough to take in the extra moisture. Cracking is most common with a heavy rain after a long dry spell, though this was not the case here because we have had an unusually rainy August. As typically happens, the fruits closest to ripeness cracked.  The cracks in the fruits provide an entry point for bacteria and fungi, and typically the fruit will rot quickly—in fact, I tossed one really rotten tomato before taking the picture.

Can you prevent cracking? You can’t prevent cracking from extreme storms, but you can prevent losing tomatoes due to cracking, by harvesting tomatoes most susceptible to cracking. Green or very unripe tomatoes are less likely to crack, so picking those that are ripe or nearly so before a big storm is a good way to prevent cracking. Since I was away during the last storm, I picked a lot of ripe or nearly ripe fruit right after I got home. You can prevent cracking if the problem is dryness by watering regularly.  You also can reduce cracking by growing tomatoes in raised beds, which drain more thoroughly than in-ground gardens, and by applying a layer of compost or other mulch to keep soil evenly moist in dry periods.

Are there tomatoes that don’t crack? Yes, there are some varieties that resist cracking. (Those that crack the most tend to be heirloom varieties and large tomatoes.) You can find a long list here of crack-resistant varieties. Popular varieties that crack less include Arkansas Traveler, Celebrity, Big Boy, Big Beef, Summer Sweet, Sungold and Yellow Pear. If cracking tends to be a problem with your tomatoes, you may want to choose a crack-resistant type.

What about calcium and cracking? Calcium helps tomatoes regulate their intake of moisture, and a shortage of calcium in the soil is also linked to blossom end rot, another really discouraging tomato problem. Some gardeners add crushed eggshells to the planting hole, antacid tablets or a commercial calcium to increase the calcium available to plants. Consider a soil test before you heavily supplement the soil.

We have more rain in the forecast for the next couple of days, so I will be harvesting more tomatoes today. How are your tomatoes doing during this rainy period?

Recipe: Garden Ratatouille

For a simple ratatouille, you'll need onions, zucchini, eggplant, peppers, garlic and herbs.
For a simple ratatouille, you’ll need onions, zucchini, eggplant, peppers, garlic and herbs.

Ratatouille may be one of the most delicious late-summer garden recipes. Traditional ratatouille includes eggplant, zucchini, onions, peppers and tomatoes, but since the dish is essentially a vegetable stew, you could add green beans, yellow squash or anything else that is fresh and suits your fancy.

A while ago, I paid a visit to Sam Kedum’s Nursery in nearby Hastings to buy some tomatoes for preserving. While I have had a decent crop of tomatoes this year, it has not been huge and most of the tomatoes I grew were slicers that have been quickly consumed in salads and on BLT sandwiches. At the nursery, which includes a community-supported agriculture farm, I also bought cherry tomatoes for drying (recipe to come next week) and some peppers, eggplant and zucchini, which looked firm and delicious.

You can find lots of recipes for ratatouille on the web and mine is a modified version of Alice Waters’ take. Feel free to adjust vegetable and seasoning amounts to suit your own taste and veggie supply.


1 medium eggplant, cut into 1/2 inch cubes

1 onion, cut into 1/2 inch cubes

1 large or 2 small zucchini, cut into 1/2 inch cubes

2-3 colored peppers, cut into 1/2 inch cubes

5 Roma tomatoes, cored, peeled and cut into 1/2 inch cubes

2 cloves garlic, minced

2 TBSP tomato paste

1/2 cup  white wine (optional, but tasty)

1/4 tsp red pepper flakes

1/4 cup olive oil

salt and pepper to taste

Cut pieces about the same size.
Cut pieces about the same size.

Cut up the eggplant first, then salt the pieces and set them in a colander to drain for about 20 minutes. (Cut up the rest of the veggies while the eggplant is meditating.) After 20 minutes, rinse the eggplant and pat the cubes dry. Heat up a large pan — I love my big cast iron skillet — so that’s a good choice, if you have it. Add about half of the olive oil. Add the eggplant cubes in a single layer and cook for about 3 minutes. Then, move the pieces around for another 3 minutes and remove the eggplant from the pan. (It will be only semi cooked.)

Add a bit more of the oil to the pan and add the onions. Season with a bit of salt and pepper and cook the onions for about 4-5 minutes, stirring often until they are translucent. Add the garlic and cook for another minute. Push the onion, garlic aside (but still in the pan) and add the a bit more oil to the pan and add the zucchini. Let it sit in one layer for about 3 minutes to get a bit of brown on it, then stir with the onions for another 2 minutes. Add the peppers and stir everything around together for about 3 minutes. Add more salt and pepper if you like and the 1/4 tsp of red pepper flakes. Push the veggies to the sides of the pan and in the space in the center, squirt about 2 tablespoons of tomato paste. Move that around with your spoon or spatula for about a minute to cook the paste a bit, then add the wine and the tomatoes. Stir the eggplant back into the mixture, and let it all cook together for about 10 minutes.

Ratatouille could be eaten as a main course with cheese on top or as a side dish to grilled chicken or fish. The flavor improves upon sitting, so leave it in the fridge a day or so for optimum deliciousness. I planned to take a photo of the finished product, but we ate it all before I had a chance.

What’s your favorite way to eat your fall vegetables?




Why is Your Tomato Harvest Down? Blame the Heat

Why  do my tomato plants look so stellar and yet have very few fruits? That’s been the big question among gardeners this year, and the short answer is blame the heat.

Blossom drop is a fairly common problem with tomatoes (though not the problem I usually have). What happens is that your plants look great, with lots of green foliage, put out plenty of blossoms, and then the blossoms just wither up and drop off the plant. I noticed this happening almost a month ago.

tomato blossoms
In high heat, tomatoes will drop their blossoms. Don’t panic — new blossoms will come when temperatures drop.

I learned from several Master Gardeners that the combination of high temperatures and high humidity—exactly the weather pattern we have been stuck in for several weeks—is a frequent cause of blossom drop. Tomatoes like daytime temperatures between 70 and 85 degrees F and they don’t like the humidity to be above 70 percent. We’ve been in the 90s frequently and above 70 percent humidity regularly.

Moreover, the amount of rain we’ve had and its tendency to come in deluges could be washing away some of the nitrogen the plants need, also contributing to blossom drop. I’m growing a few tomatoes in pots and a few in the ground, and the ones in pots got a good shot of worm-poop fertilizer a couple of weeks ago, so I do not think that is my main problem.

I’m hoping the weather may correct itself soon and the plants will get a chance to set more fruit. In the meantime, I’m coddling the few tomatoes that are ripening on the vine.

Bruschetta Variations: Bruchetta with Goat Cheese and Garlic

With the tomatoes starting to come in, I made bruschetta and eggs for dinner last night. Bruschetta is toasted Italian bread with a topping, often including tomatoes and olive oil, that is typically served as an appetizer.  Last year, I made Bruschetta a la Julie and Julia after watching a movie about Julia Child and the blogger who cooked every recipe in Mastering the Art of French Cooking. (The bruschetta scene is positively mouth-watering.) Since then, I’ve seen bruschetta recipes with everything from bacon to peaches in them. The variation I tried last night is not quite traditional, but close

toast with goat cheese and tomatoes
Yum! A new way to make bruchetta.

Bruschetta with Garlic and Goat Cheese

For the topping, cut three to four ripe tomatoes in smallish pieces, and mix with 3 tablespoons olive oil, 2 tablespoons chopped fresh basil, salt and pepper to taste. You can add a splash of vinegar, if you like things tart. Let this mixture sit out on the counter for a half hour or so to blend the flavors.

Toast slices of Italian bread. We used a whole grain version, but use whatever you like as long as it is sturdy. Rub each slice lightly with a clove of garlic. Spread with chevre or another goat cheese. Top with topping and enjoy!

This was very good, but whoo-boy, the garlic I used was very fresh from our local CSA farm and pungent. After dinner mints required.

Best Bets for Beginning Vegetable Gardeners

I spent most evenings over the past week digging through the stacks of seed catalogs that have been arriving at my house since Thanksgiving. While I probably get more catalogs than most gardeners, it struck me how daunting it is to decide what to grow, if you are a beginning vegetable gardener.

So — as a gardener who has watched lots of plants die or just sit there — here are some suggestions of sure-fire, almost-no-fail vegetables to plant.

  • bowl of tomatoes
    There’s nothing as fun as tomato time in the garden.

    Tomatoes. Nothing, but nothing in the store is as nice as a fresh tomato from your own garden. The best bets for the north are the cherry types (can’t beat Sweet 100s for reliability) or any of the pear tomatoes. I had great luck with Beam’s pear last year and am trying a mix of red and yellow pear tomatoes this year. A totally reliable slicing tomato is Celebrity.  It’s an All-American Selection winner from 1984, is widely available as a seedling, resists most diseases, and performs well even in somewhat poor conditions.  If you want to make tomato sauce or salsa, try ‘Roma.’ I’m going to grow ‘San Marzano‘ this year, which I’ve heard is very reliable as well. Newbie gardeners should buy starts (little tomato plants) rather than trying to start tomatoes, peppers and other warm-season crops from seed. Tomatoes need warm soil — something we don’t have in Minnesota until about June — and it’s a hassle to start seeds inside (it’s fun, but a hassle), so go to a local nursery or the farmers’ market and buy plant starts there. The farmer or nursery employee will be able to offer advice, too, on when and where to plant the seedlings.

  • pole beans in garden
    Pole beans produce a longer harvest than bush beans.

    Green beans. Another easy plant to grow. Get a bush variety so you don’t have to hassle with setting up a trellis or pole tepee. Some of the most reliable are Provider or French Filet. If you want to grow pole beans because they require less space, try Blue Lake or Kentucky Wonder. Like tomatoes, beans do not like cold soil. Wait until it’s getting warm before you plant them, and keep an eye out for bunnies. My beans were nibbled to the nubs last year by rabbits. This year, I’m putting a wire fence around the bean bed.

  • Zucchini.  Zucchini is so sure fire, I almost hate to mention it. Plant this summer squash (any variety will do) and you’ll soon be leaving grocery bags of it on unsuspecting neighbor’s porches.
  • Lettuce. Seed providers have really gone crazy with lettuce mixes, so try one. I’m planting ‘Farmer’s Market Blend‘ from Renee’s Garden, but there are dozens of options. Lettuce can be planted early, just keep it moist and don’t plant it all at once. You want to plant every couple of weeks in the spring, then take a break, and plant again in August for a fall crop.

    Leaf lettuce in bowl
    Leaf lettuce is great in spring and again in fall.
  • Raspberries. If you have room, and you want big gratification for little effort, plant raspberries. A trellis will keep them neat, but raspberries are a bramble — which is a close cousin to a weed — so plant a few bare-roots and watch them produce. I grow ‘Anne‘ and ‘Caroline’ and love them, but there are many good varieties for the north. 2018 Update: The increase in spotted wing drosophila in Minnesota has made raspberries an iffy pick. If the SWD is in your area, avoid raspberries.

Those would be my picks for a first garden. What would other gardeners plant if  they were planting their first vegetable garden?

Yellow Tomato Jam

It was 42 degrees F this morning when I rode my bike into downtown Northfield, so tomato season cannot last long. Late last week, I harvested what will probably be my last pile of tomatoes off of the Beam’s Yellow Pear bush that has been so prolific and delicious this summer. I’ve had problems with my other tomatoes, but the yellow pears have been great.

jam in jarsSince I had more than I thought we’d eat in the next day or two, I decided to make Yellow Tomato Jam with them. There are a bunch of recipes for this jam at various cooking sites. This one sounds good, if you like things spicy, as does this one. I modified this recipe to make my jam.

Yellow Pear Tomato Jam

  • 4-6 cups pear tomatoes, cut in half with as many seeds removed as is easily possible.
  • 1 lemon
  • 1 orange
  • 4 cups sugar
  • 1 package of pectin
  • Nutmeg, cinnamon, cloves, salt

Prepare the tomatoes and place in a large pot. Grate the lemon and orange zest into the pot, then remove the pith and put the flesh of the lemon and orange in the pot, add a good shake of nutmeg, cinnamon, a dash of salt and cloves. (Heavy on the nutmeg, light on the cloves.) I also added a half cup of water, too, because things were looking dry. Add the pectin, stir, and heat until boiling, stirring occasionally. Dump in the sugar all at once, stir until mixed, and let it boil for 10-15 minutes. It will get thickish. Meanwhile, prepare your canning jars and lids and get a big pot of water boiling on the stove, preferably canning size. Put the jam in the jars, wipe rims, apply lids, and process in a boiling water bath for 10 minutes. (If you don’t like to can, you could probably freeze the jam as well.)

This jam is like a marmalade because of the orange and lemon and the spices. Very good on toast or on a bagel with cream cheese.

A Tough Year for Tomatoes

During my visit to the Minnesota State Fair, I had a chance to chat with the Minnesota Master Gardeners staffing the extension booth in the Horticulture Building. I asked what was the most frequent question they were getting at the fair. The answer: Why do my tomatoes look so bad? Many gardeners (including yours truly) are experiencing blossom-end rot on their tomatoes.

According to the Master Gardeners, fluctuations in moisture and too much fertilizer are the most likely causes of blossom-end rot. “Tomatoes don’t like too much nitrogen,” one of the MGs reminded me. I’m seeing blossom-end rot mostly on my paste tomatoes, which are in a new bed to which I added lots of compost. (Oops.)  For best results with tomatoes, don’t grow them in the same place more than once every three years. Interestingly, my best-performing tomatoes are yellow pears, growing in a mixed bed in which I have never grown tomatoes.