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?



Growing Vegetables in Raised Beds (and What’s Going on With This Soil?)

One of my backyard gardens is on the site of a former garage. We removed the one-car garage last summer and replaced it with a larger building to store cars and tools. The site of the former garage is now where I grow vegetables in raised beds and am trying to grow some perennials, shrubs and vines on the extremely poor soil.

The tomato has a fruit, but it’s so small, you can tell its struggling. Photo take July 15.

Raised beds can be a terrific way to grow vegetables, but as I am finding out, your beds are only as good as the soil in them. Witness the photo at left. The bed this sad tomato was planted in was one of two that were filled with a soil mix that was labeled as being specifically for raised beds, including those with vegetables. I planted beans, parsley, tomatoes, squash and marigolds in the two beds—in late May/early June. For weeks, they have sat there. And sat there.

With the exception of marigolds, which seemed to be growing a tiny bit and are flowering, none of the plants were thriving—or even growing much. On many of them, the leaves turned yellow. Nothing has up and died yet, but they sure have been struggling. Witness the photo below, a small raised bed (with less sun than other raised beds) where I used an organic bagged soil mix and some manure. These tomatoes and basil plants were roughly the same size as the ones in the other beds when they were planted a few weeks ago, yet they are growing, producing flowers and fruit and generally doing what a plant should do. (Update: Since I wrote this post a week or so ago, these tomatoes have grown so much I’ve had to lash their trellis to the fence.)

Planted in a bagged soil mix, these tomatoes have grown so much I’ve had to tie them to the trellis. Photo taken July 15.

So what’s up? It could be the plants have gotten too much water, but given the size of the beds and the dryness of the top 3 inches of the soil, I doubt that. I checked out this article on what yellow leaves on plants means and my yellow leaves don’t perfectly match any of the pictures—though they are close on a couple of them.  A couple of weeks ago, in absolute frustration, I decided to add some more nitrogen to see if that helped. One bed got composted manure; the other got liquid fertilizer. The plants have grown more since then—one of the beans has finally latched onto the trellis I want it to climb and a few bean flowers have emerged.

I also sent a sample of the soil to the U of M Soil Testing Lab to find out exactly what kind of soil I’ve got here. (I contacted the landscaping firm that sold me the soil, but have not heard back from them.) The U turned around the soil test results quickly and I found out that while the mix had a good percentage of organic matter (12.5 percent), it had sky-high levels of potassium (that’s the K in the N-P-K ratio on most fertilizer bags.) Potassium’s main role in plant growth is to regulate how other nutrients are taken up by the plant and to regulate certain processes. Too much potassium in the soil will interfere with up-take of nutrients such as calcium and magnesium. The U recommended I add nitrogen but nothing else to the soil to improve plant growth.

One of the main reasons to grow vegetables in raised beds is that you can control the soil better. In my case, the dreadful soil that was already on the site made growing vegetables impossible without raised beds. If the beds are tall (mine are about 14 inches tall), they should be treated like a container, with regular watering and fertilizing to enrich the soil. Needless to say, come fall, I will be adding leaves, compost and manure to all my beds in hopes of getting the soil in better shape for next year.

Do you grow vegetables in raised beds? What’s your favorite soil mix?

Fall Container Idea

Fall container completed in less than 20 minutes.
Fall container completed in less than 20 minutes.

A week or so ago, while I visiting my daughter in Chicago, I happened upon a fun idea for a simple fall container. The container (shown below) was on display at the Morton Arboretum in suburban Chicago. The container itself was large, wide and made of terracotta. It was filled with an assortment of gourds and squashes. Simple, and very pretty.

The inspiration for my fall container
The inspiration for my fall container

I knew that was an idea I could easily replicate at home, and I had just the container to do it with. A couple of years ago, I bought a small, metal horse trough to use as a planter. I ended up making it into a small water feature this year, which I had emptied out a few weeks ago.

At the Northfield Farmers’ Market last Friday, I found an assortment of squashes. One of the sellers was also selling bouquets made of ornamental cabbage and kale. Cute! I bought one and decided to use it as an accent in the container. The kale and ornamental cabbages are basically cut flowers, so I needed to keep them in water. To set up the container and keep the squashes elevated, I flipped a couple of pots over and set them in the trough. Then I filled a couple of tall canning jars with water and placed one in the back of the container and one in the front.

Pots elevate the gourds and a jar of water keeps the kale fresh.
Pots elevate the gourds and a jar of water keeps the kale fresh.

I put the kale in the water jar in the back and three of the cabbage in the water jar in front. The squash were balanced on the upside down pots. It looked nice, but I had one more cabbage and a pumpkin left. I put the cabbage in another jar of water set inside a colorful container and set the pumpkin down in front of the trough. Voila! Instant fall container.

Once I had everything bought, putting the container together took less than 20 minutes.

I’ve tried a couple of fall container ideas before including planting a pumpkin here and here. What’s your favorite fall container idea?

Fall container in less than 20 minutes!
Love the texture in this arrangement.

Five Tips for Great Container Gardens

At last week’s Northern Green Expo, I had a chance to hear DeAnne Bennett, a garden maintenance consultant with Bachman’s, talk about how to create and maintain fabulous flower beds and containers. The plant combinations she puts together for homeowners in the Twin Cities are breath-taking. But, she clearly has a practical streak, too, and her advice on how-to build a container is worth passing on.

A big striking container doesn’t need much help in the garden.

1. Use a big pot. Large containers require less water and look more impressive. So as long as the size is proportional to your house, go big. To keep her containers from being too heavy to move, DeAnne uses non-biodegradable packing peanuts on the bottom of quarter to third of the container, then covers the peanuts with landscape fabric. The pot drains well and the soil and peanuts are separate from each other. You can often find packing peanuts free, and by separating them from the soil, you can reuse them.

2. Add organic matter to the soil mix. For her containers, DeAnne mixes one-third organic matter, such as compost, with two-thirds potting soil. With an adequate supply of nutrients from the organic matter, you won’t need to fertilize as much — once a month or less.

3. Pick plants based on conditions. Sure, you wouldn’t plant a sun-loving moss rose in deep shade, but think about other conditions as well when choosing plants.  For instance, if it is windy in your area, consider annuals such as fuschia or lantana or wind-tolerant perennials such as yarrow or shasta daisies.

container in rock garden
Another container tip: Place them in the garden. They fill in empty spots with color.

4. Stop fertilizing when it’s dry. Don’t force a stressed plant into overdrive. Just keep watering and wait for a break in the heat.

5. Toss your potting mix. This is a bit controversial — I know many gardeners who re-use the soil from containers from year to year — but DeAnne says, it’s done its duty and is now dead — so toss it and buy new.


Pretty in Pots

The ‘Spitfire’ nasturtiums I’m growing as part of the bloggers’ Seed GROW project have really taken off in this container area near my front door. I love nasturtiums for their big showy foliage, but these also have vibrant orange blooms that stand out in my otherwise green, pink, and purple garden.

I planted the nasturtiums in three different areas of my garden: the container area, which gets morning sun and is otherwise shady; a little spot near the garage, which gets morning sun but has tough clay soil; and near a pergola in back in a flower bed with rich, black soil.

Flowers peeking out from behind foliage.

In terms of bloom and height, the container nasturtiums are way ahead of the rest. They began climbing the simple wire trellis I put in the pot, with just a bit of encouragement from me. (I wound the plant tendrils around a few wires and tied one main stem loosely to the trellis.) The plant now covers much of the trellis and is spilling out of the pot. It  has been blooming for a couple of weeks. The orange flowers are bright enough to be seen from the street and are a great illustration of the power of orange.

“I’m growing Nasturtium “Spitfire” for the GROW project. Thanks, to Renee’s Garden for the seeds.”

Holiday Containers on the Cheap, Part 2

With the weather about to cool way down, I didn’t want to wait to put together a mixed holiday container. It’s easy to spend a lot on items like packaged spruce tips, curly willow sticks, red twig dogwood and even faux berries and poinsettias, but you can also do a mixed container for very little money. For this mixed container, I started by using a collage technique to decorate the plastic pot with holiday paper.

This takes a day or more to do, so over the weekend, I also gathered the fixings for my pot. I bought a small Fraser fir Christmas tree for $15 (this will be used in another project as well) and cut the bottom 1/3rd of the branches off for the main greenery in my pot. The Fraser fir has kind of two-toned needles, which adds a nice texture to the pot. I also walked around our yard, cutting stray branches from a swamp white oak and a mugo pine. I like the wispy look of red cedar in holiday containers, but don’t have any in our yard. We do, however, have a very mature creeping juniper, so I snipped some wisps from that to use. I had some left over grasses that I had used in a Halloween display as well. The grasses had a large reddish seedhead, so I thought they would add something to the pot, too.

holiday container and red twig dogwood
A blend of textures gives the pot a cheery feel.

This morning, assembly began. First, I filled the pot with leftover potting soil from this summer and began building the greenery around the pot. I started with the Fraser fir, then added in the white pine, the mugo, and the juniper for accents. It looked pretty good, fluffy and green, with a fair amount of texture. Then, I added in the red-headed grass (if anyone knows what this is called, please let me know through the comments) and some Joe Pye weed from the garden.  I tried several ways of placing it, but no matter what I did, the grass looked, as my husband said as he left for work, “dead and sad.” That’s not what we want this time of year!

With the grass out, I needed something else to brighten the pot. This is the first year I’ve had hydrangeas and I’ve been looking forward to seeing the snow on their broad flowerheads, but it seemed a good idea to sacrifice some of them to the pot. The tannish brown color contrasted nicely with the greenery and the flowers added another texture. The pot still needed some brightening. The pot has a natural look to it, so ornaments and ribbon seemed out of place. Instead, I put skewers into a couple of apples and stuck them in the front of the pot, and cut several branches of berries from a high bush cranberry bush.

The finished product contrasts nicely with the tall red-twig dogwood display and gives a cheery look to our front porch.

apple greenery hydrangea bloom
Apples added a fresh touch to the container.

How to Create a Holiday Pot on the Cheap

red twig dogwood in container
Red twig dogwood harvested from the yard and a tall pot is the ultimate cheap holiday container.

It’s easy to spend a lot of money on holiday decorations for inside and outside of your home — but it can also be done on the cheap, and my goal this holiday season is to come up with a few nice decorations that don’t cost much money.

Here’s the ultimate cheap holiday pot: It cost nothing. A couple of weeks ago, I trimmed back some decidedly overgrown red-twig dogwood bushes. While many of the branches went to the county brush pile, I picked some of the longest, straightest, and brightest for use in outdoor holiday decorations.

For this simple pot, I took a good-sized bunch of branches and set them in a strawberry pot that otherwise would spend the winter in the garage. Ta-da! A decorative holiday pot.

A Bouquet of New Books

I’ve been so busy in the garden and with work that I haven’t had much time for garden-related reading, but four new books worth mentioning recently came my way.

Two of them are part of a series of regional gardening books put out by Lone Pine Publishing, a Washington-based publisher of gardening and how-to books. Herb Gardening for the Midwest, by Debra Knapke and Laura Peters, is an herb-by-herb guide to growing and using herbs from basics like basil and parsley to the unusual. Has anyone heard of orach? According the Knapke and Peters, it tastes like a mild spinach and can be used to treat sore throats and jaundice. If you are interested in herb gardening, this would be a good, basic book to buy. It’s a soft cover and costs $19.95.

Container Gardening for the Midwest by William Aldrich and Don Williamson, with Alison Beck and Laura Peters, follows a similar format to the herb book. It opens with an introduction to the basics of container design and upkeep, then goes plant-by-plant through a selection of annuals, perennials, shrubs and trees that can be grown in containers, everything from arborvitae to yucca plant. I like that Williamson, who Minnesotans may know as co-author of several books on gardening in Minnesota with Northern Gardener columnist Don Engebretson, and company do not restrict their plant choices to the usual suspects. For instance, they recommend growing blueberries in a container, which makes a lot of sense since blueberries require soil much more acid than Midwestern gardens usually have–so why not manage the soil better in a container? Also, soft cover, $19.95.

British publisher Cico Books recently released Quick and Easy Container Gardening by Tessa Evelegh. The book includes step-by-step instructions for 20 container projects. This is more of a “pretty picture” book and the photographs by Debbie Patterson are beautiful. The book also leans toward gardening as decorating, so if you want an idea for using containers for dinner party decorations or finding cool containers at junk stores, this is the book to check out. Again, soft cover and $19.95.

cover of birding bookThe last book is probably my favorite of the lot, but it’s not out yet. I received an uncorrected proof of Rodale Press’ new Best-Ever Backyard Birding Tips, by Deborah L. Martin. This is 300-plus pages of advice on how to create a bird-haven in your backyard, with information on everything from providing cover to growing the plants birds love. It includes profiles of individual birds, including those most commonly seen in Minnesota. The book has several nice features, including tips for attracting birds on a budget and “myth-busters” that address common misperceptions about birds. For instance, their feet will not get stuck on a metal perch in cold weather a la Ralphie’s friend Flick’s tongue in the best Christmas movie ever made, A Christmas Story. Best-Ever Backyard Birding Tips will be released in late July, and speaking of the holiday season, it would make a great gift for any birders or bird-loving gardeners on your list.

Fun with Wood

It’s still too early to be tromping around in the garden, so the great weather on Saturday seemed like an invitation to finish some garden building projects. So, after picking up some deck screws and 2-by-2 posts at the local lumberyard, I started work on my new raised bed. (I bought the cedar for the sides last fall.) This bed will be 3-feet-by-5-feet and will be devoted to tomatoes.

upside down raised bed
A raised bed under construction

I’ve built raised beds myself twice before, and several years ago, my dad built a pair of them at my old house. His beds turned out nice and square–mine, not so much. I followed the guides set out by Sunset books on how to build the bed. I liked the idea of putting the posts down and basically building the bed from the top down. To put it together, I used deck screws. It worked better for me to drill a pilot hole for the screw, then to put it in and use my power drill to install the screw. This bed is 11 inches deep, with a 3-1/2 inch board on top and a 7-1/2 inch board underneath. (In the photo, it’s upside down.) On the next sunny day, I’ll go out and dig the holes to fit the posts in, and fill the bed with soil. The mix that I have heard recommended is one-third garden soil, one-third compost, and one-third sand. The Sunset guides indicate you can put the bed together in a few hours, which proved true. However, I’d recommend having someone around to hold the boards in place while you are attaching them. With the long boards especially, it’s tricking to keep them in position without a little help–hence, my somewhat trapezoidal bed.

The other job I finished is the building of a frame to use to hold up my raspberry canes. For the frame, I used four 1-by-2 boards with a pointed bottom, and four 2-by-2 boards for cross-beams. I will be adding eight hooks and then running wires between them. The idea is to create two channels of wire through which the raspberry canes will grow. The frame is supposed to improve air circulation and make the raspberries easier to pick by keeping them at eye-level. When I was installing the frame on the raspberry bed, I noticed that the raspberry canes left standing over the winter had buds on them. With any luck, there will be a July crop of berries, as well as the early fall crop that we had last year.