The first year in our apartment, I enthusiastically planted many, many seeds, with some successes and more failures. We moved in during wintertime and I didn’t realise how far the sun would come around the building to blast our south facing patio space.
Many of my plants died from too much sun and not enough hydration. I’d planted them in pots too small or the wrong material to retain moisture at the roots. I’d come home on a 30 degree day to find my plants shrivelled and parched. A good drenching would bring them back to life (sometimes), but it’s better not to stress plants out like that – even I know that.
Self-watering planters to the rescue?
When I learned about wicking, or self watering planters, I was intrigued. Many people told me it changed their gardens. Wicking beds use a reservoir underneath to hold a tank of water that plants can suck up as needed. This keeps them hydrated on scorcher days and saves water. In spite of Sydney’s past week of heavy rain, Australia is never far from drought.
Self watering planters open up opportunities for growing in places that aren’t easy to water (verge gardens for example) or those that don’t get much rainfall. Wouldn’t it be great to have micro community gardens on the verges and untended patches in our cities?
The only issue I had with the wicking beds was cost. I found many beautiful options to buy or build that ran into the hundreds, which I was not prepared to spend. I searched high and low on the web for inexpensive DIY designs. I talked to people who’d had some experience making them.
I had a breakthrough when I mentioned my struggle to a friend who works at a childcare centre. He showed me how they’d installed beds using simple plastic tubs set into wooden frames. Sidenote: cool childcare centre! This seemed achievable and just the right size for my place. I decided when found the requisite materials secondhand, I would make a go of it. When I came across a 60L lidless plastic storage container at Salvos, I knew it was time.
Materials I used to make my self watering planter
- 60 L plastic container $5
- 1/2 bag blue metal gravel $4
- 1 bag scoria $23
- 1 bag charcoal $8
- 1 1/2 bags compost soil $6
- Coles reusable bag – free
- Hessian sack – free from any coffee roaster
- Segment from a broken hose – free
- 1/2 old cotton sock
- Rubber band
The materials came to a total cost of $46 + the seedlings. The cost would have been much less if I had bought the $8 scoria instead of the $23 scoria, but live and learn.
How I made my self watering planter
First I prepped the plastic container. I made a thumbnail sized hole ⅓ the way up the side, about 12cm from the base. I don’t have a drill so I spiralled the end of a pair of scissors until it bored through. This worked easily after a minute or two. The hole is to let water flow out when there is enough in the reservoir.
Next I made the reservoir. I made sure to move the box to where it would live before filling it. I used scoria (a type of porous volcanic rock), charcoal and then gravel for drainage, but you could use sand or just one of these fillers instead of three. I think a finer grade fill would be better, which is why I used charcoal to fill in some of the spaces between my coarse fill. I added the materials up to the same height as the hole in the side.
I should’ve done the next step before I added the rocks, but yeah, we learn as we go around here. I used a bit of a broken hose as the watering pipe and dug it into the rocks . Most tutorials suggest PVC piping. The purpose of the pipe is to deliver water directly into the reservoir, but it’s okay to water from above too, as rain would. A wide PVC pipe also shows you the water level in the bottom so you can see if you need to add more. My hose won’t help with this and truth be told might be difficult to water into. If it really becomes a problem I’ll go get a proper pipe and replace it.
I wrapped the bottom end of the hose with a piece of an old sock to avoid it clogging with particles of charcoal, rocks or soil.
Then I placed a layer of material over the reservoir. The purpose of this is twofold: to keep the soil separate to the reservoir and to help wick the water from below to the soil above. I used an old reusable shopping bag that I cut to open, and then a hessian sack overtop to fill any gaps and help with the wicking action.
Finally, the fun part – plants! I added the soil and my seedlings. In this case, sugar snap peas, lettuce, lemon thyme and basil. Most tutorials advise to water through the watering pipe until water flows out of the outflow, but it’s been so rainy that I didn’t bother and simply gave the transplants a little drink from above. I hope some of these will grow enough that I can bring cuttings to the crop swap I’m organising in November.
It was a fun outdoor project for the brief moments of sun we had this weekend. It’s been a long winter without much garden time and I’m happy to be back picking dirt from under my fingernails. I’m no expert. I don’t know if this will work as hoped. Surely it’ll work better than my dried out beds of the past and help me keep my plants alive when I’m out of town for stretches at a time. I’ll let you know when I’ve had a chance to test it through the hot spells to come.
One final note for us apartment gardeners dependent on bagged soil. Redcycle will accept clean, dry soil bags cut into smaller squares, and seedling containers can be reused or recycled. Check with your local council or nursery about the best drop off point.