If you’re longing for a garden but are lacking land, container gardening could be a perfect way to bring ornamentals or vegetables into your space.
Aaron Steil, Iowa State University Extension horticulture specialist, joined Garden Variety host Charity Nebbe to share solutions for renters, people with shady lawns and anyone else looking to bring plant life and color to their home without digging up a plot.
“Decks and patios, those kinds of spaces which we spend a lot of time in potentially and would be nice to have, you know, annuals in bloom and those kinds of things during the growing season,” he said.
Container gardening is relatively simple to set up and putting plants in accessible places can also make gardening easier for people with mobility difficulties, said Steil.
Choosing a container
Any container with a drainage hole that allows excess water to get away from the soil can work for gardening. Steil said the excess water should be able to drain in five to ten minutes, and two to four holes should be sufficient drainage for most containers.
“The other thing to keep in mind is that in almost all situations a container is going to look smaller outside than it does in the store or in your house,” Steil said. “And so while a six inch container for a house plant is nice on your windowsill, you put that out on a deck or even a front stoop and it's really small… Most of the plants we’re growing in containers outdoors, like annuals, put on a lot of growth over the growing season. So, in most situations, the larger the container, the more easily you can have success, the less you're going to be watering. And really often what we end up doing is balancing the cost of the container and the potting soil versus the size. And often I try to get the largest one I can do looking at the cost.”
There are beautiful options at local garden centers, but if you want something cheap and simple, a five-gallon bucket with drainage holes is a great starting option.
Picking a soil
You do want to invest more money in your soil choice, as potting soil is a better option than topsoil.
“When you go to the store and you see that $2 bag of topsoil versus like the six, seven, $8 bag of potting soil, it's very tempting,” Steil said. “But when we put garden soil or topsoil in a container, it functions differently than it does when it's in the earth. And it has very poor drainage typically.”
Steil also cautions against putting rocks at the bottom of a container as a substitute for a drainage hole. Adding a layer of rocks actually brings the wet part of the container closer to the roots, which won’t help your plant.
Most plants will need fertilizer at some point since there are finite resources in the container.
“While many potting soils will have slow-release fertilizers incorporated in them, most of the time, in a typical situation by midsummer — that has been used up.”
Ideally the fertilizer you add should be full of nutrients that plants need, including nitrogen, phosphorus and potassium. Fertilizer bags have numbers on the front indicating the ingredient ratio of those nutrients. Steil recommends using fertilizer with a relatively even ratio number.
You won’t need to repot your container with new soil each year, but eventually the soil will start to break down and stop draining well. Steil recommends once every five or six years to pull everything out and start over.
Watering
Container gardens do require additional attention when it comes to watering.
“They are some of the higher-maintenance things in our landscapes if we have containers, and watering is the big reason why.”
Early in the summer season you can get away with watering once or twice a week. But as plants grown and roots fill the soil volume, Steil said you should be checking on these plants more frequently, especially as the temperature warms.
“By August, often I'm watering containers every day. And those ones that were too small, or are in really exposed locations and too small, I'm maybe watering in the morning and the afternoon."
The good news about container gardens: if your plant isn’t happy being too exposed to the sun, you can easily move it somewhere else.
Types of plants
When it comes time to pick out what to plant in your container, Steil says ornamental annuals are great for containers.
“Many of them are selected or bred specifically to use in containers, so they'll have more compact growth habits, or you know, have a slightly slower or more full growth habit or rate. And so annuals like petunias and begonias, ageratum and sweet alyssum are great. Of course, the classic annual geranium is wonderful in a container. There are several different annuals that can do quite well all growing season in that situation.”
If you’re hoping to grow vegetables in your container, place the plant in full sun, meaning there will be six hours of sun rays per day hitting the leaves.
Small, quick growing vegetables are best for containers, such as lettuce and other greens.
“There are other things that are a little more challenging in containers just because they get so large. But we can find compact varieties of those plants, so instead of using an indeterminant, heirloom tomato in a container — which can get so very large — we can find a determinant or a more compact growing cultivar.”
