My two-year-old helped me plant the bean screen last week, as part of our first week of firstspring. Here’s what it looks like:
This is a small-space gardening technique I’ve been working with. The idea is that we put climbing plants in the block wall, and they go up the bamboo stakes and up the string to provide an extra shade and visual screen across the front door. I’m very conscious of the need to block heat from entering the house for six months of the year, so I had planned to make a plant screen across the front windows before we ever moved in. When we did move in I had a better look at the layout and space and realised the only spot with sufficient space and overhang to make a good screen was this little space along the thigh-high brick wall at the front door. Which doesn’t actually need a screen, but I wanted to do it anyway.
The cinderblocks are hollow, and I’ve stacked them so that each plant can access the full depth of the block wall but can only access one block’s width. Most of the climbers I’ve grown aren’t happy unless they’ve got at least 30 cm depth, they need the root depth to get vertical height. They also prefer not to be too crowded. This is a bit half-and-half as far as crowding goes – the plants don’t have to share a space so they’re not crowding each other, but the space is a bit small. The blocks protect the soil from heat quite well, but they can suck moisture from the soil so I still have to watch for dryness and the hydrophobia and excessive runoff that comes with it.
I’ve tried a few different plants, but my best success has been with Purple King climbing beans. In my climate beans will grow for most of the year, and Purple King are a prolific fruiter. Whatever you plant, this last is important if you want to harvest a crop. The small growing space per plant – and the inevitable neglect when you forget about them for a couple of weeks because you see them every day and so stop remembering they exist – means that fruiting and harvest will be significantly reduced. Half of a prolific crop is no longer prolific but it’s still reasonably productive. I’ve also grown climbing peas with some success and was considering sweet peas, but they’re really a winter plant here and I’m happy to have the light coming through then. I tried planting leeks last autumn, just for a non-leguminous winter fill, but had no luck – will see what happens next autumn. Climbing tomatoes are something I’ve considered but decided against them for this space, partly because the screen’s location at the overhang limits the light the plants receive and partly because I have them growing prolifically in the back yard already.
I’ve found that pests aren’t too much of a problem in a wall like this – most pests don’t find their way to the plants too quickly (as long as you haven’t planted brassicas). The exception is snails. This kind of cinderblock wall is actually the kind of habitat they build to protect endangered snails. They love it. Having tasty seedlings on top for a handy lunch is just a bonus. I lost quite a few seedlings to snails during their active season before I wised up to the problem, which meant I only had half a screen last summer. Seedlings planted after the snails are beginning to aestivate in secondspring, or before they wake up in autumn, do fine. The other way to solve the problem is to make it an opportunity. This year I plan to try and harvest snails as a secondary food crop if I can get a holding terrarium organised, so my bean screen will actually be a kind of bait to attract them to my frying pan. I can almost guarantee that as soon as I want snails up on that wall that they won’t come within six feet of it.