Posted on May 18, 2023
Gardening season is upon us again and many fruit and vegetable gardeners have already started planting both seeds and seedlings into their garden beds and greenhouses. It’s an exciting time for those of us who thrive in the dirt. Today’s blog isn’t dedicated to the seasoned gardeners, though, but to those of you who don’t have the space for a big garden bed but want to give it a whirl anyway. Let’s talk about container gardening.
To begin I'm going to let you in on a not so secret, secret: gardening in Calgary is not for the faint of heart. Inconsistent weather patterns, hail, soil types, microclimates, and the fact that Spring never seems to start at the same time each year, means there will always be a little trial and error. It sounds more daunting than it is, and I only mention it so you know it’s not you if something doesn’t go as planned. Once you figure out what works best in your location, you will have a lot of fun watching your plants grow and eating the fruits of your labour. The benefits to container gardening are you have more control over soil, it is easier to cover in the threat of hail, and plants can be moved around if necessary (and if the container isn’t too large). There is no need to feel limited by container gardening, either. Many plants can be grown in pots and grow well. Most food bearing plants need at least 6 hours of sun to grow and produce. To find the best spots for your containers, take a couple of days to watch the sun’s movements around your home. It is also important to remember that containers tend to dry out faster than in-ground gardens, so plan to water daily if it doesn’t rain and, on really hot days, possibly twice a day. Some plants need a longer growing season, so for things like tomatoes or peppers your best option is to pick up starter plants from the local garden centre. For other foods, like lettuce and beans, you can start from seed and still have plenty of time to harvest.
One constant for growing vegetables is rich, well-drained soil so roots can spread deep and to avoid root rot. It is also important to replace the nutrients plants use to grow, especially in pots where their soil quality is limited by what you do to each pot. Here are a few easy home-made fertilizer ideas. Along with fertilizer, flowering vegetables like tomatoes or squash, need calcium added to the soil. Calcium helps prevent blossom-end rot. Finely crushed eggshells (food processor is good for this if you have one) mixed in the soil or make an eggshell water. I will highlight some of the easy to grow plants, but in the end, you are only limited by your imagination. If you want to try something other than what is written here, do it! If it doesn’t work this year, make some adjustments and try again next year. If you find yourself wanting to delve deeper into the gardening world, you can join the Calgary Horticultural Society and gain access to many great workshops and other resources.
Tomatoes: Cherry tomatoes are great because they take less time to mature and you can use them in so many different dishes, but any type of tomato can be grown in a pot. Your container for tomatoes does not have to be overly large. 1.5-2 feet deep is enough. Last year, my neighbour used old metal wash basins that were a foot deep for his first gardening attempt and did great. Tomatoes like a hot, sunny location and you will need to stake them as they grow or use a tomato cage. These can be found in most garden centres. Years ago, another neighbour (who grew massive tomato plants every year) told me to plant them again a fence or wall to maximize on the heat bouncing off the structure. It’s has been great advice. To maximize your fruit abundance, you will want to prune or pinch leaves throughout the season. This is not a daily task, but one that can be done every couple of weeks, and honestly, I don’t start doing this until later in the summer and the plant is large. At that point there are a lot of tomatoes on the vine, so I pinch any new leaves to redirect energy towards the existng flowers and fruit. In the end, it’s not a step to sweat over. If your tomato stem bends or breaks once you get it home, don’t give up. Tomato seedlings easily grow roots from their stems wherever they contact soil. Replant the stems right up to the leaves, and they will grow more roots.
Beans: Both bush beans and pole beans can grow in a pot. Pole beans you will need to have something for them to climb up, either a trellis, bamboo sticks, or sturdy string. They can get very tall, so make sure you have the space before choosing pole beans. Bush beans tend to produce faster and take up less space. Beans are easy to grow in a multitude of conditions. In my 15 years gardening I have always had reliable bean harvests, no matter the variety I choose. Keep watered, especially when the plant(s) start to flower.
Carrots: Growing carrots in a pot is not as common but can be done very successfully. Carrot root lengths vary, so pick a pot that will accommodate the variety you have chosen. The deeper the pot the more room roots have to grow. Carrot seeds are very fine, and I find it impossible not to over seed. Though carrots don’t require a huge growing radius, they still need space to mature, so once your leafy carrot tops are about 2-3 inches tall, thin out clusters or you’ll end up with a group of barely bite-sized carrots. Carrots don’t like it too hot, so keep in mind you may want to move them when the mid-summer temperatures get too much, especially if your growing space is west facing and in the hot afternoon sun. Carrots don’t like to be saturated with water, but they do need consistent moisture in the soil. Water when the first inch of soil is dry. If carrots get drought-stressed they tend to fork or twist. You will also want to keep an eye on the tops. If you see them pushing up through the dirt and becoming exposed, pile some soil on to cover up (called hilling). Exposed tops can turn green and become bitter. Carrots get sweeter as the weather gets colder, so though you can harvest them as baby carrots over the course of the summer, leave a bundle into the fall if you like the sweeter crunch.
Greens: Lettuce, kale, spinach, and other leafy greens I liken to weeds, because once they get going you have to eat it or give it away, because they just don’t stop. I prefer to grow Russian kale (it’s leafy like lettuce), romaine lettuce, butter crunch, and spinach. These crops do not like it too hot and can be grown with other plants that would offer some protection. The roots are small, so they are an easy food to share space with another plant or create a pot of multiple green varieties. My leafy greens are the plants I get the most continuous use out of. It is also an easy plant to succession seed over a few weeks, to have a continuous supply.
Peppers: Whether you’d like to have bell peppers on hand or something with a little more kick, you can grow your peppers in pots. Like tomatoes, the pot should be a minimum of 1.5 feet deep. Smaller peppers can get away with a slightly smaller pot. Peppers like full sun and heat and are another good candidate to place against a wall or fence where the heat from the sun can bounce back onto them. Peppers typically don’t like to dry out, so keep an eye on the soil. Also keep an eye on the plant becoming top heavy. It may be necessary to stake a larger plant before the peppers weigh it down. Harvest when ready and enjoy!
Potatoes: I have grown potatoes in soil bags and now in containers. When I used soil bags, I bought a large bag of potting soil and cut holes all over it to stuff potato seeds into—which can be purchased at most garden centres or you can use the potatoes in your cupboard you forgot about that have started to sprout from the eyes. If larger, cut them in half, place cut side down. You want 2-3 eyes per potato seed. The plastic helps keep moisture inside, so you can water less, and the tops grow out of the holes. It's pretty fun to watch. I have also seen people use reusable grocery bags and I now use a large, deep pot. There are some cool dedicated potato pots you can purchase that allow you to harvest from the bottom throughout the season. You can also create your own potato containers by purchasing 2 of the same containers and cutting large holes into one. Nest the two, with the modified one on the inside. Whatever potting method you decide to use, add soil, potato seeds, and water. The bigger and deeper the pots or bags you use, the more potatoes you will get. It’s no potato field, but my family still gets a pretty good harvest out of it. Potatoes like 6-8 hours of sunlight, but are a good vegetable for northern growers, meaning it doesn’t have to be a hot hot summer to get a good crop.
Squashes: Squashes have much of the same potting needs as tomatoes. Many varieties will vine out, but if you add a trellis for them to vine up, they can still work in a smaller space. You can also get “bush” or “compact” types that will take up less space. Squashes require pollinators to move the pollen from the male flowers to the female flowers, so if your pots are on a balcony not frequented by our friends, you may have to hand pollinate. Only female flowers produce squash, but they must be pollinated or the tiny fruit at the base of the flower will wither and die. It's really quite easy, though. First identify which is the female and which is the male flower. Using a Q-tip or something similar, gather pollen from the male flower (it will come off yellow and a little powdery) and then gently move it to the centre of the female flower.
No matter what plants you decide to try or how many containers you can fit in your space, have fun and enjoy the journey!