At this point in the season, tomatoes are either doing great or tipping toward disaster. So in addition to offering some growing tips to help make tomatoes happy and healthy, I’ll explain some of the common things that can go wrong.
Probably the most important thing you need when growing tomatoes is sunlight—8 hours or more is best, but 6 will allow plants to produce a fair amount of fruit. If you don’t have a spot that gets even 6 hours of sun and someone is home a lot during the day, consider buying a few round, rolling plant stands. I got mine (which look like metal Frisbees on wheels) at Ikea, but most garden centers sell them now, too. Put your tomatoes in large pots, set them on the rolling plant stands and move them into the sun as it moves throughout the day.
Soil is key to tomato success too. They thrive in healthy soil, so it’s a good idea to work some compost and composted manure into the area before planting. If you’re planting in pots, just add those things into your potting mix. Halfway through the season, scratch a little more compost into the top of the soil around plants, but don’t add more manure. Too much nitrogen (N) will give you lots of leaves and little fruit. You want a fertilizer with more potassium (K) than nitrogen in it. Phosphorous (P) can also be on the low side, usually, since compost supplies a good amount of that. Product labels always show the N-P-K ratio like this: 10-10-10 or 5-2-1. You want something more like: 1-0-4 or 1-1-3. Seaweed (powdered or liquid kelp) is a great choice and is usually 1-0-4.
Tomatoes like water, but not too much. Water plants deeply but not so often, or so much, that you end up with soggy soil. That can lead to disease problems and, later in the season, to tomatoes that don’t taste like much because all that water got channeled into the plant’s fruit. If you’re growing tomatoes in pots, stop watering when you see water running out of the bottom of the pot. Watering consistently, every few days in hot weather—more often if plants are growing in pots—will also help prevent the dreaded blossom end rot. You know you have this common problem when your tomatoes have black spots on their bottoms. Consistent watering allows the fruits to get the calcium they need from the soil to develop properly.
Did you bury the stem at planting time? If not, do that next year by gently plucking off the plant’s branches below the top flush of leaves. Depending on the size of your transplant, you’re usually burying 2 to 6 inches of stem, and that’s a good thing because new roots will sprout all along that stem and help your tomatoes be strong and healthy.
Pruning tomatoes doesn’t need to be as complicated as it is often described. Tomatoes are classified by growth habit: determinate tomatoes—also called bush tomatoes—are bred to be more compact, usually about 4 feet tall while indeterminate varieties—also known as climbing or vining types—can grow to 6 feet tall or more. Determinate tomatoes don’t need much pruning beyond removing all of the suckers below the first flower cluster. Indeterminate tomatoes benefit from some pruning, but you don’t need to grow crazy. Basically, if you pinch out suckers and pare plants down to around stems, you’ll get bigger fruit and less sprawling growth. If you let plants be more unruly than that, you’ll get more fruit but you’ll have to deal with a more tangled mess of vines. Either way if fine, so don’t sweat it a whole bunch.
Are the leaves on your tomato plants curling up in hot weather? Don’t worry, that’s probably not a disease. It’s just how some tomato varieties react to the heat. This type of leaf roll usually starts on lower leaves and works its way up. It doesn’t look great, but it shouldn’t affect fruit development. Watering regularly and mulching the ground beneath your tomatoes can help keep this problem at bay.
Well gardener friends, at this dark time when we are up to our eyeballs in bad news about pretty much everything and politicians are compounding our worries by behaving like raised-by-wolves toddlers, let me offer a spot of sunshine. In case you haven’t heard, two positive things have happened for the planet—or at least our local slice of it—in recent weeks.
Good thing number 1: At long last, the Minnesota Department of Agriculture has confirmed that neonicotinoids, a commonly used group of pesticides, are highly toxic to honeybees—even when they are used in accordance with the law. How is this good news? You ask. Well, despite mounting evidence, the suggestion that neonics are likely one of many things contributing to the decline of honeybees remains heatedly disputed.
Now, investigators from the state Department of Agriculture have found that in fact the hives of two beekeepers were decimated by toxic dust that drifted from the cornfield of a neighbor. The seeds the neighbor planted had been coated with clothianidin, a neonicotinoid that is routinely used to coat agriculturally grown corn and soybeans in the United States. The insecticide protects the seeds from insects in the soil. It also protects the plants themselves because all parts contain the toxin, making the whole corn or soybean plant poisonous.
According to a Star Tribune story on March 20, Bayer CropScience, the maker of neonic pesticides, has acknowledged that toxic drift from cornfields planted with treated seeds can be harmful to bees and other pollinators. However, they say the problem is rare. Beekeepers and bee researchers beg to differ, countering that drift is a common and ongoing issue.
Both beekeepers will be compensated for the loss of their hives under a 2014 law that enables beekeepers to collect damages even though, technically, no law was broken because seed treating is not currently considered a pesticide application. What? Anyway, yes there is much to be done on this issue, but the Department of Agriculture’s action makes Minnesota the first state to declare, as a finding of fact, that neonics are harmful to bees.
Fellow gardeners, the seeds available to us are not coated with neonics, but we can continue to do out part to help bees and the Earth by saying NO to plants that are sprayed and/or soil-drenched with the neonicotinoid pesticides. Ask before you buy. Together we can make a change.
Good Thing Number 2
On March 16, the Minneapolis Park and Recreation Board (MPRB) voted to stop using glyphosate (the active ingredient in the weed killer, Roundup) in neighborhood parks. Activists have been calling on the park board to ban chemical use in Minneapolis parks for several months. (See the Southwest Journal story I wrote on the issue in October for more information.) Little progress has been made so far. But during a park board meeting on the 16th, more than 40 people showed up to voice their opposition to the use of pesticides, herbicides and other chemicals in public parks. Many others called and emailed.
This public outpouring of concern about the health effects of glyphosate and other chemicals, in addition to a recent update board members received on when and where staff use chemicals, seems to have sparked the move to stop using Roundup. But eliminating the use of one chemical in neighborhood parks is a long way from the shift to chemical-free, organic park management that activists would like to see.
In the absence of glyphosate, which has been increasingly linked to health and environmental problems, the board is free to continue using many other pesticides and herbicides that could potentially cause harm. The vote also allows them to continue using Roundup in regional parks at Lake Calhoun and Minnehaha Falls, as well as on ball fields and golf courses.
Based on what has been said about the issue, only commissioner Brad Bourn is openly in favor of moving to an organic approach to managing Minneapolis parks. Commissioner John Erwin strongly supports reducing the use of chemicals. The rest of the board—all of them elected by the public—don’t seem to see chemical-free parks in our future. Do you? If so, now is the time to email the commissioners, particularly Scott Vreeland, who has repeatedly said this is an issue that only activists care about. From what I hear from neighbors and readers who frequent our parks with their children and dogs, I am certain he is mistaken.
Want to grow vegetables and herbs even though you don’t have full sun? No problem. You just need to choose edibles that don’t depend on six hours or more of baking sunlight to thrive. So, yes, tomatoes are out, as are peppers, squash and eggplant, because plants grown for their fruit really do need a minimum of six hours of good sun per day.
But that still leaves a wide variety of edibles to choose from as long as you’ve got more than deep shape to work with—not much will grow under a maple tree’s canopy. But plants grown for their roots and flowers will produce with as little as three to six hours of full sun or consistent dappled sun. Beets, carrots, broccoli, cauliflower, onions, turnips and radishes, for example, can be successfully grown with four to six hours of sun. And though they produce fruit, I get a pretty good crop of cucumbers in 5 hours of sun.
Leafy veggies like kale, spinach, leaf lettuce, arugula, mustard greens and Swiss chard can get by with only two to four hours of sun—though they will grow more lush in sunnier locales. If you have a garden that offers both sun and shade, one of the advantages of knowing what can take less sun is the ability to increase your harvest by tucking these plants in along shaded borders that are often though of as wasted space.
Sure, there’s a lot to be said for the power of sun, but there are some benefits to growing vegetables in part shade. Crops like broccoli and cauliflower won’t bolt as quickly as they would in full sun, tender lettuces will last longer and you won’t have to water constantly, which is always a plus. That said, though, it is important to monitor moisture levels in shade gardens carefully because these sites are often located beneath big trees or shrubs, as well as the overhang of the house or garage. So even when it does rain, the water may not reach your garden, and much of what does fall will likely be taken up by the root systems of greedy trees and shrubs.Read More»
If I were able to retire tomorrow, one of the first things I would do is read more. I already read a lot: I love books. But I could read a lot more if I didn’t work so, fingers crossed that we win the lottery sometime soon so I can get to the stacks and stacks of books taking up space all over our house.
One of the things I did manage to do recently was catch up on the books I’ve received to review. Here are some of my favorites. First, though, you’ll notice these books are not the latest, hot-off-the-press sort of thing. I read as I’m able and review some of what I like. If I don’t like something, I take my grandma’s advice to “not say anything if I can’t say anything nice.” I figure, just because I don’t like a book doesn’t mean you won’t. Why be a spoiler?
Beautifully Sustainable: Freeing Yourself to Enjoy Your Landscape (Be-Mondo Publishing, 2013), by Douglas Owens-Pike. I met Douglas several years ago when he invited me on a mini tour of some of the Minneapolis gardens his landscape design firm, EnergyScapes, had created in recent years. All of them were lovely and different from most “designed” gardens in the sense that were very natural, consisting mostly of native plants and arranged as if Mother Nature had done it herself. True to his company’s name, the landscapes were all created with resource conservation in mind.
Beautifully Sustainable (which can be purchased here: http://energyscapes.com/book/) is Douglas’ attempt to help gardeners at all levels make their landscapes more sustainable, and his smart, clearly explained ideas and tips are very useful. But I also appreciate how on a more subtle level, his book helps readers think more like a designer when visualizing outdoor areas: What sort of space would I really enjoy? What features matter to me most? What view do I want to see from my living room?
All of these questions seem easy, and they are. But most of us don’t think of them until the patio is poured or the pergola is built in what turns out to be the totally wrong place. “Take time to imagine,” he wisely suggests, before explaining how to create a map of your landscape long before you buy the first plant. Other chapters cover things like how to build healthy soil, create a rain garden, get rid of weeds without chemicals and how to maintain a landscape once its planted. In other words, there’s something for everyone in this helpful, enjoyable book.
For those who want to learn more about growing edibles in our climate, take a look at Emily Tepe’s The Edible Landscape: Creating a Beautiful and Bountiful Garden with Vegetables, Fruits and Flowers (Voyageur, 2013). Emily was doing fruit research at the University of Minnesota when she created an edible demonstration garden and fell in love with growing food.
There are lots of things to love about Emily’s book, but in particular I appreciate the way she accompanies her advice to incorporate edibles into gardens with colorful illustrations that show exactly how that can be accomplished beautifully. While the book is a general primer on growing edibles, the appendix includes an extensive list of edible plants specifically for northern gardeners. I found several varieties there that I’m going to try this year.
Gardeners who want to help support pollinators and other beneficial insects should check out Minnesota landscape designer Heather Holm’s fantastic book, Pollinators of Native Plants (Pollination Press, 2014). While the text sometimes made me reach for my botanical dictionary and refer to the glossary in the back of the book, Heather really did a great job of conveying complex subject matter in a relatable way. Don’t want to learn about the actual process of pollination? Skip to the descriptions of the many different creatures that visit flowering plants. Read up on bees and how they live and work together. Or jump right to the bulk of the book where native plants are described in detail along with the insects that are partial to them. The photos alone are outstanding.
But the information Heather offers about natives for three distinct habitats: prairies, woodland edges and wetland edges, can be used by all gardeners who want to attract pollinators. And isn’t that all of us at this critical time?
I generally try to avoid writing a lot about the same issue for fear of boring people to death or seeming like a nutter who can’t stop ranting about one thing or another. In the case of neonicotinoid pesticides, though, I’ve received so many calls and emails on this topic since I started writing about it a few months back, I feel like updates are wanted and needed. So I’m going to go with that feeling and tell you more about what I’ve learned lately in hopes that this will help answer some questions you may have now that you’ve likely learned more about this issue too.
First, here’s a quick recap for those who don’t yet know about neonicotinoids. Neonics, as they are often called, are a class of pesticides that have been linked to the decline of bees, particularly honeybees, over the last decade. Because they are safer for humans than some other pesticides, neonics have become widely used in the nursery trade as a pre-treatment for annuals, perennials, shrubs and trees. They are also found in many of the common pest control products gardeners buy off the shelf and use every day for everything from Japanese beetles to emerald ash borer. (Neonic pesticides include: imidacloprid, acetamiprid, clothianidin, dinotefuran, nithiazine, thiacloprid and thiamethoxam.)
Now that studies have shown that small amounts of neonics can harm bees feeding on the pollen and nectar of treated plants while larger doses can kill, more and more gardeners are making it a point to stop using products that contain neonics and to shop for plants that haven’t been treated with the pesticides. I’ve heard from a lot of people who have called, visited and emailed garden centers and nurseries locally and nationally asking about the use of neonics.
Stories vary widely with some places eagerly sharing their plans to discontinue their own use of neonics and to seek out suppliers who will do the same. But I’ve also heard reports of a fair amount of denial and defensiveness. What you need to know is that it isn’t enough for a retailer to say THEY are not using neonics any longer on the plants that they grow. You also need to know whether the plants they get from outside suppliers are neonic free. Getting that information will take willingness and time on the part of the nursery and from what I’m hearing, it’s clear that not everyone is putting in the effort.Read More»
Of all the things in our landscape, I think the galvanized cattle troughs (also known as stock tanks) in our backyard get the most attention. Even in the winter when nothing is growing in them, their shapes and sheer size turn heads and provoke questions. We added them to what we’re now calling “our little farm” a couple of years back when we lost a huge oak, and I figured I’d take advantage of the sun to grow some vegetables. After starting with one trough, we added another last year and we’ll be getting one more in the next few weeks.
If you want to grow some food on a small, urban lot, you can’t beat these troughs for being easy to get going. You don’t have to build anything, and you don’t have to deal with turning depleted urban soil into something safe, nutrient-rich and workable enough to grow food in. They’re also affordable, durable and tall enough to be out of the way of hungry critters and peeing dogs.
People ask all the time where we got the troughs and how to turn one into a raised bed garden, so even though I wrote briefly about this a couple of years ago, I thought I’d explain the process more in-depth here since it’s the perfect time to get raised beds going for the season. Let’s start with where to buy them. Unless you are literally made of money, do not go to a boutique garden center for a livestock trough. You want to go where farmers buy stuff—Tractor Supply Co. and Fleet Farm.
If you want to grow things like tomatoes, peppers, beans and squash, get yourself a large trough. One of ours is four feet long and the other is six feet. Both are 2 feet wide and 2 feet deep, and they cost about $80 and $110, respectively. Aside from getting the things home in the back of the car, the biggest job is drilling holes in the bottom for drainage. Use a bit that can drill through metal that’s about the size of a dime of nickel. We drilled holes every few inches all around the outside edge along the bottom, and then added many more holes going across the bottom of the trough from end to end and side to side. Remove the drain plug, too, since you won’t be needing it.
Once you’ve got your holes drilled, flip the trough over and put it wherever you want it because once you fill it with soil, you won’t be able to move it around without taking most of that soil back out. We don’t like things looking all kittywampus so we used a level to make sure the trough was lined up properly once we got it situated. (You don’t have to do that unless you’re bugged by such things.) Now comes the soil part. My advice—don’t cut corners. Good soil makes all the difference when you’re growing anything.
Because these are containers, albeit huge ones, you want a mix that’s going to drain well. You also want to provide plants with some nutrients that you’ll boost over time by adding compost and fertilizer. You’ll save some money if you make your own mix by combining 1 part topsoil, 1 part compost and 1 part coconut coir or coarse sand (also known as builder’s sand). I’ve done this by combining these things in batches in a wheelbarrow and it worked well. But I’ll admit, it’s a heck of a lot less work to call someone and have a quality potting mix delivered to your driveway. That way, you can just shovel it into a wheelbarrow and take it right over to your trough and other containers.
What do I mean by a quality mix? As I’ve said in the past, I’ve learned a lot about soil and compost over the last few years and I’m now opting to go with products that are organic or at least produced by a company or farmer who is willing to explain their process so I can make an informed decision about whether to use it. (For much more on that topic, see my blog post on safe compost.
Local organic growers give products from Purple Cow Organics, COWSMO and Mississippi Topsoil high marks. Other local sources that come highly recommended are Kern Landscape Resources and Kelley and Kelley Nursery. Compost from our Linden Hills organics recycling program is also pretty good. But because it includes packaging, paper and other odd bits, I don’t use it to grow edibles. That’s just me. Keep in mind that even though it’s costly to fill your trough with quality potting mix the first year, in subsequent years (unless you get some dreaded disease like early blight of tomatoes) you’ll only need to add a bit more compost to keep soil healthy. If you feel like you’re having drainage issues, add more coir or sand. With the hard part behind you—all you have to do is keep growing.