17 March 2008
Containing yer gardening enthusiasms Part 2: Tips for Success
Last time, I promised we’d have a chat about some tips for container successes, so here we go:
Containers: You can use just about anything you want for containers, and people do! I’ve seen wonderful planters made with old shoes, tea kettles, vases, baskets, purses, as well as the dizzying array of containers that are actually designed for plants. The main thing to make sure of is that they have drainage holes. Don’t bother with the ‘layer of crushed gravel’ or other supposed helpful options for drainage: if Jeff Gillman says that this doesn’t work, that’s plenty good enough for me. A pot shard over large drainage holes will keep the soil from coming out the bottom, but that’s all I bother with. If you buy a fabulous container that is lacking drainage holes, you can either drill holes in it (with the proper drill and bit) or do what I do: plant into a slightly smaller, plastic container with drainage holes in it, and slip that into the more ornate planter. Larger containers are heavier, but they have more room for multiple plants. I'm very partial to terra cotta, and to brightly coloured, glazed pottery containers in a variety of shapes and sizes.
Soil: use the best quality potting medium you can afford. You can make up your own mediums or purchase pre-made, but one thing I don’t recommend is using garden soil. Not only is it full of weed seeds and living creatures that might not appreciate life in a container, it’s generally heavier which makes containers that much harder to move around. You can make up good potting medium using a mixture of screened compost, sand, peatmoss or peat substitute (I’m not weighing in today on the peat argument) and perlite or vermiculite.
Watering: This is definitely one of the secrets to container success: making sure that you don’t let your containers dry out. This means watering daily, in most cases, depending on the time of year and the climate. Come autumn, when the plants have slowed down growing and days are cooler, you might not have to water daily; it just depends. Grouping containers together helps to keep moisture in the containers so you might not have to water quite so often. Some gardeners recommend adding those moisture-holding crystals, but they’ve been shown not to be particularly useful, so I don’t bother with them anymore.
Fertilizing: You can mix slow release fertilizer, organic or otherwise, into your potting mixture before planting, but you’ll still need to fertilize later in the season. I usually toss bonemeal and seaweed meal into my container mixtures along with some compost, and then water with liquid seaweed fertilizer once every two weeks. When you do fertilize, make sure that you have watered the plants well before fertilizing, or you can burn your plants roots.
Plant selection and care: as hard as it is to do, the theory goes that we’re supposed to select young, healthy plants that aren’t yet blooming for our containers and gardens. The theory makes sense, of course: plants that aren’t yet blooming tend to settle in to new conditions (whether in gardens or containers) because they aren’t focusing their energy onto creating flowers and seed. But when we’re starved for colour, it’s hard not to buy the plants that are already putting up flowers, isn’t it? Well, you’ll really thank yourself if you do buy plants that aren’t yet flowering, or if you disbud those that are forming flowers. Trust me on this. Within a couple of weeks, those new plants will have settled in and be flowering nicely. This is where it helps to have a greenhouse or other place to hold your containers for a couple of weeks while you are waiting. And you can always buy or create a couple of planters already in flower, just to help you get through the early weeks. I’ve been known to do that, too.
Deadheading is vital for prolonged bloom; after all, annuals are programmed to flower, set seed, and die, so if we prevent them from setting seed, they’ll keep flowering, determined to have their progeny live on after them. While you’re deadheading, you might also remember to cut container plants back a bit every week or so to encourage a new flush of growth and keep your plants looking lush and healthy. Somewhere, someone told me to use think thirds: cut back a third of a plant to a third of its height every three weeks. I might not get the every three weeks part right, but I remember to trim plants a third at a time, and they seem to do quite well. That’s my story and I’m sticking to it!
Next time: some tempting plants I love in containers. But first, since it's now St. Patrick's Day, at least in Nova Scotia...