Sub Irrigated Planters - Rooftop

I have always enjoyed growing my own food in the summertime. It's easy to do and nothing tastes better than a freshly picked tomato! However, we moved into an apartment with no garden/yard and I was unable to plant out for a few years. We did not have a garden but I did have access to a flat roof. But I still needed water and a growing medium? That's when I decided to make a rooftop garden using Sub Irrigated Planters! Sub Irrigated Planters are self watering containers/beds that use a soilless potting mix.

Utilising scrap wood left over from various projects, I slowly collected all the materials I would need, including recycled food grade 5 gallon buckets that would be used as the containers. Firstly I created a level, fenced-in structure to keep out the local wildlife and protect from the strong North winds. It would be somewhat protected and face due South with uninterupted full Sun all day. Then the fun began!

I decided to use Sub Irrigated Planters (SIP's) to reduce the amount of water I had to get up to the roof every day, and also reduce the overall weight of all the components on the roof itself. The Sub Irrigated Planters work by keeping a reservoir of water in each container to stop the plants from drying out. They also use a soilless mix that retains moisture and wicks water up to the plant. I took this a step further and connected each container in series, with a pipe. This allowed me to water one container, which would slowly in turn fill all the others creating the reservoir.

You can make Sub Irrigated Planters out of any container you have to hand. I used recycled 5 gallon buckets, some Rubbermaid Totes, and made a planter from scrap wood and an old Tarpaulin. The containers were drilled with a Hole Saw to create 'air holes' around the sides and allow each one to be connected for water supply. I used a Marine Thru-Hull and a Bicycle innertube to make the connection.

The containers are each lined with a 'reusable' shopping bag to hold the mix of coir and potting mix. Coir is coconut fibre retains water and is an excellent wicking material when added to potting mix. The reservoir keeps the containers from drying out so even on the hottest days the plants were never in any danger. The roof also boasts uninterrupted full sun which really powered the plants.

I was able to grow Tomatoes, Peppers, Kale, Zucchini, Cucumbers, Lettuce, Arugula, Herbs even Strawberries and got a great yield from everything that year, using a liquid fertilizer added to the water supply for simple application. They were only fed/watered from the bottom up, and the plants only took what they needed. The rooftop garden was a great success and I was encouraged to develop further with the SIP idea. If like me you love growing food but have no access to a yard then SIP's may be the way to go? With a few simple items you too can grow your own food!