As a gardening experiment last month, I made a few wicking boxes for my front balcony. It faces east, across the River Derwent and while the view is lovely, it gets all the morning sun and can be quite windy. This time of year, we can’t walk on the concrete in bare feet before 2pm! I’ve grown salad greens in containers out there since I moved in, over six years ago but it’s a lot of work and difficult keeping water up to them with baking sun and drying winds.
I started out buying two food grade plastic crates from my local hardware store (I think they were 23 litre size), the kind that are often used as recycling boxes. All other materials were either recycled or things I had on hand.
Old hose was spiked with holes and laid in the bottom, with the refill end slotted into a length of larger diameter poly pipe to make it easier to pour water into. It looks pretty ugly but it works!
Next, I put a layer of gravel over the hose, making sure the refill end didn’t get buried as you can see in the photo. By the way, this gravel wouldn’t be my ideal but it was sitting in a pile begging to be used up and there was just enough to do all the boxes 🙂
At the top of the gravel, I carefully drilled a small overflow hole diagonally opposite the refill hose. This means water won’t build up and start getting smelly and the plants won’t rot in overly wet soil.
Next, I covered the gravel with some old tea towels that weren’t really wonderful for wiping dishes anymore. They allow the water to pass through but not the soil. Eventually, they will rot away and I’ll have to replace them but it was good to recycle them. Old shade cloth would be ideal if you have it.
At this stage, I put a thin layer of good quality potting mix over the top, and I recommend not cutting any corners with this. The better the soil, the better the plants! I mixed well rotted sheep poo and plenty of mushroom compost in large bucket and worked this through layers of potting mix until the box was fairly full. The result was a friable, rich mix, perfect for quick growing summer salad veggies.
I made sure the soil was damp before planting out the first seedlings and watered them overhead for the first couple of days, until the water reservoir started to do its thing. I ended up doing eight boxes in total and crammed in fast growing Pak Choi, Portulaca, Red Amaranth, Grumolo Verde Chicory, Garland Chrysanthemum and even Silverbeet. The results have been fabulous
The pic above was taken 15th December 2015 and the pic below a month later, the 14th January 2016. The results have been incredibly successful and I’m only having to refill the reservoir about once every three or four days instead of overhead watering morning and night. Despite the fact salad is my favourite meal of the day, I can barely keep up with the amount of food these boxes are producing!
Do you grow vegetables in containers? What are your top tips? Please leave a comment below – I love to hear from you all!