Anyone who has tried starting a garden in Alberta knows that our climate can make it a unique challenge and gardening tips that work in other parts of Canada don’t always cut it here. That’s why this June, we’re sharing one plant description every Friday from Alberta gardening books and plant guides. Today’s Flora Fridays feature comes from The Prairie Gardener’s Go-To for Vegetables by Janet Melrose and Sheryl Normandeau.

These two are Calgary authors and gardening experts—Melrose runs the consulting company Calgary’s Cottage Gardener and both are regular contributors to The Gardener for Canadian Climates magazine, among other publications. In this book, they answer practical gardening questions in Q&A-style with easy-to-understand instructions, like a friendly FAQ page for your Alberta garden that you can turn to time and time again. And better yet, it’s the first in a popular series that’s been on the Edmonton bestseller list consistently all spring, so there’s more where this came from!

Potatoes

Does a potato plant have to flower to produce potatoes?

Not all potato varieties will flower. (Some will do so only occasionally.) A lack of flowers will not affect tuber production, so there’s no need to worry.

Many gardeners use the old adage to wait about three weeks after the potatoes have flowered to harvest, which is problematic if the plants don’t flower. The easiest thing to do is excavate a small area of soil about four inches (ten centimetres) from the base of one of the plants to see if there are any tubers there. (If there aren’t any, dig a little bit closer to the plant’s roots.) If the tubers are not the size you desire, let the plants continue to grow for a bit longer.

Hilling potatoes—is it necessary? If so, how is it done?

The practice of hilling your potato plants works to increase yields. If you hill organic material around their stems, you increase the amount of room the underground stems have to grow, which leads to the potential for increased productivity. The additional covering also prevents tubers from forming close to the surface of the soil and being exposed to sunlight and photosynthesizing, which causes tubers to turn green and form toxic alkaloids in the skin, making them bitter.

The simplest way to hill potatoes starts with planting seed potatoes in a trench about twelve inches (thirty centimetres) deep that has been well dug over and has additional organic material added. Place your potatoes at the bottom of the trench and cover with soil. Once they are well established, about six inches (fifteen centimetres) high, fill in the trench so that just the top leaves are exposed. As the potato plants get bigger, keep repeating until they have grown out of the trench. At this point, you can continue to add soil around their stems or switch to a mulch, such as straw. Keep mounding soil or adding mulch around the plants until they start to flower, or until you run out of organic material, energy, or time.

Using a mulch for the last hilling works to keep weeds at bay, deters potato beetles, keeps the roots cooler, and conserves moisture in the soil.

The practice of growing potatoes in bags, mesh cylinders, and potato condos is based on the same technique of hilling, except you are using an above-ground container. The disadvantage of these containers is that the roots can either dry out due to evaporation around the sides or become too hot. After all, potatoes are meant to be a below-ground root vegetable. The benefits are all in the ease of harvesting as you simply tip over the container. No more putting your garden fork through the biggest potato!

A way to mitigate the downside of an above-ground container is to dig a hole the width of the container and sink the container into the hole at least partially, which serves to keep the roots cooler and yet keeps the convenience of harvesting.

One last word: Please do not use tires to grow potatoes. Some tires have many chemicals that can leach out into the soil and contaminate your potatoes. There are many much better options!

Excerpt by Janet Melrose and Sheryl Normandeau from The Prairie Gardener’s Go-To for Vegetables, copyright © 2020 by Janet Melrose and Sheryle Normandeau. Reprinted with permission of TouchWood Editions. 

At the end of June, we are giving away a prize pack containing the gardening and plant guides from our Flora Fridays series including The Prairie Gardener’s Go-To for Vegetables by Janet Melrose and Sheryle Normandeau. Sign up for our newsletter to win! If you’re already signed up, you’re already entered! This giveaway is open to Canadian residents.