Top tips for container gardens
We’re at the starting line for garden planting, and container gardens are right up at the front of the pack.
Some folks have braved our anything-goes spring weather, and already have their pots and planters filled with greenery and flowers. Condo and house residents alike are creating colour and growing food along walkways and on their balconies, patios and front in pots and window boxes.
What pitfalls should be avoided? How can you get top performance from your container-grown plants — the best colours, the most butterflies, or the tastiest tomatoes? We can lend you a hand with some advice:
Should I use last year’s soil?
No. The nutrients in last year’s soil are used up, and it might be carrying spores for various root-bound diseases you do not want to carry over. Time to refresh and revitalize using a quality mix that is designed and blended for container use.
Do not throw last year’s soil out, put it in a ground garden and if you don’t have one, give it to someone who does.
Clay or plastic pots?
We prefer clay as it breathes, transpiring moisture through its porous surface in exchange for oxygen. All plants like this arrangement. But it does mean that you will water a little more frequently than you would with plastic.
How do I choose plants for my containers?
Ask yourself, “What am I trying to achieve?” A potted wildlife garden containing bee balm, echinacea, and marigold will attract beneficial insect and butterflies.
If you just want colour, look for plants that suit the sun and wind exposure of your containers’ location. It sounds simple but it is surprising how often people get this wrong.
If you are growing food, like a tomato plant, give it enough space and sunlight to perform. A tomato plant will need two bushels of soil to grow well, which is more than most people realize.
Is drainage important?
Drainage is the #1 consideration when choosing a container. There should be a minimum two cm hole for every square foot of soil surface. For any plant to perform well, water must move through the soil and out the bottom freely. Don’t forget the pot saucer to catch extra water.
How do I know when to water my container plants?
While there is a wide variety of demands for water, depending on the plant type and species, our general rule is to push your index finger into the soil up to your second knuckle. If it is cool and damp, hold off. If it is dry, time for a good drink.
Water thoroughly, and less often, rather than giving a sprinkle every day. Most herbs perform well when allowed to dry between watering since this minimizes the odds of root rot or fungal-borne disease.
Do I need to fertilize my container grown plants?
Most quality container soil mixes contain slow-release fertilizer, or enough organic content in the form of compost that no fertilizer is generally necessary until about midseason. As plants grow, their roots eventually fill the container and there is a greater need to fertilize.
We recommend either an organic-based liquid plant food or an application of water soluble 20-20-20 every week to 10 days.
What do I do with my container plants if I’m away?
Move them into a shaded spot and water them thoroughly just before you leave. If they are too heavy to move, water them well before you go. The best course of action is to have a plant-sitter keep an eye on them, with specific instructions to minimize the risk over-watering and you returning home to rotten plants.