I'm sure we all have them: plant pots sans drainage hole(s). Sure, sometimes they can be perfectly fine as a decorative piece. But if you want something living inside it, you will need a second, hidden planter inside that does have drainage holes. But you still run the risk of root rot from standing water unless you've placed gravel or something else in the bottom of the decorative planter. So, what can you do to remedy this? Create your own drainage hole!
Many suppliers of planters seem more concerned with the decorative aspects of their wares than on the eventual good health of their future occupants. Instead of passing up a planter you otherwise like, this tutorial will show you how to fix it:
What You Need
Materials
A clean planter in need of a drainage hole
Small amount of water
Tarp (optional)
Tools
Drill, fully charged (mine is a hammer drill)
Diamond hole saw kit (can be purchased at Home Depot or other online retailers for around $20)
Hammer
Instructions
1. Gather your tools and clean, dry plant pot together.
2. Insert hole saw into drill and take the adhesive backing off one of the templates, place it on the hole saw guide, aligning the notches.
3. Then remove the other side of adhesive backing and place guide over area to drill. Without the guide in place, the drill will not stay put and can possible kick back and cause injury to you and/or the ceramic pot.
4. Begin drilling. It will probably make an awful screeching sound at first, but keep drilling while using the guide until you are at least 1/4" down. Then you can remove the guide.
5. After removing the guide, you can add a tiny bit of water to keep the ceramic and diamond bit cool, but also to help soften the pottery. Cool pottery drills more easily than hot pottery.
6. Keep drilling, taking short breaks as necessary. Depending on the thickness of the pottery, this could be totally quick, or take up to 20 minutes total. The pot I was drilling was the latter. So, I stopped 4 or 5 times to give the drill motor a break.
7. If you feel that you are really close to breaking through, you can give a sharp tap from a hammer right in the center of the circle. If you are indeed close, it should pop out quite easily. If not, you'll need to drill a bit longer. Once the hole is made, it's time to fill with your favorite potting soil and get planting!
Additional Notes: You may want to do this on a tarp, a piece of old cardboard or something else that can't be damaged. I took my chances on a concrete walkway, but I'm lucky I didn't gouge it out with the drill bit.
The diamond hole saw kit was not with the rest of the drill bits in the tool section of the hardware store. Oddly, it was in the flooring section. Keep that in mind if you have trouble finding it in the store
(Images: Michelle Chin)
(Re-edited from a post originally published 7.25.11 - CM)
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I have a lot of plants in pots with no holes. Oops. They seems to all be doing just fine though, so I'm not going to worry. =)
This may sound like a trivial tip, but I can tell you that unlike, say, a plaster wall, Rubbermaid-type containers shatter when drilled with a regular drill bit. The hole saw spreads the force around and puts less stress on the plastic. If you're going to make imitation Earthboxes or trying to grow plants in 5-gallon buckets, you'll be drilling a lot, and investing in hole saw is a good idea.
Most of the diamond hole saw bits I've used were meant to be used with flowing water and at relatively low RPMs ~700. With water and at the lower speeds you shouldn't get any screeching. You only need a trickle of water to keep the bit lubricated but more importantly cooled. Under the correct conditions the bit should not be too hot to touch while in operation. If it is you should let it cool down unless you don't mind wearing out the bit prematurely.
The main reason these bits are in the flooring sections is that they are primarily intended for cutting holes in tiles for plumbing.
Instead of boring the hole from the inside of the planter, it's probably easier to flip the pot over and drill from the bottom.
While I've added holes to porcelain pots this way, There are some advantages of using the pots as cachepots as they are intended. It's easier to switch out plantings, especially seasonal plants. In places where the summer is hot and arid it's less wasteful when watering since there is no run off. The excess water will wick back into the soil faster than it will evaporate.
The importance of drainage holes is exaggerated. Soil composition and moisture retention are more critical to mitigating root rot. Drainage holes are only really good at alleviating gross over-watering. That's why it's still easy to kill succulents and citrus with over watering if planted in common potting soil.
or... put a pile of rocks in the bottom so the water can collect down there rather than keeping your soil soggy.
@ajanhelendam - yes, i know why they're in the flooring department, but it would make more sense for them to be with the other bits...since all specialized bits aren't distributed around to the area of their specialty (i.e. the tile bits aren't next to the boxes of ceramic tile).
@hikatie - eventually, the muck in the bottom with the rocks will reach your roots (or vice versa). i'm not telling anyone they HAVE to do this, but it's really the best solution in the long run to keep your plants healthy.
This is much more complicated than the method I've always used:
1. Pour a little water in the pot
2. Drill a hole with a large masonry bit
Done. Drilling slowly with the water feels like you're just churning up mud, not drilling something hard that will break or shatter.
I can tell you that most of the pots that have needed a hole have been done successfully by drilling with a masonry bit (even without water). One step.
tbh I just avoid all the hassle by only buying pots with holes. Adding rocks to the bottom for drainage between the actual pot and the decorative container (if it's used outside) is, I find, an excellent place to later discover unsavory bugs who like moist places....and if it's been raining excessively or if you're an enthusiastic waterer, the water level goes quickly up and requires monitoring or at least regular emptying.
Masonry bit works for me, with water in the pot, and with the pot resting securely on damp soil. The method listed here is probably more fool proof.
Yes-masonary bit works just fine. I bought it at Home Depot but maybe $5? No need to spend so much $$$. I don't even use water. Steady pressure, take breaks, blow off powder...done.
Thank you so much. I've been wondering how to do this properly.
another vote for a masonry bit. no water, no drama, done.
I poked holes in mine with a corkscrew. #notagrownup
Ditto on the bit.
I had some metal pots and wanted to add a drainage hole. I went to Ace to get the equipment and they offered to just drill the holes for me!
Jess, nice service!
I tried to drill a hole with a regular bit – nope. Just a lotta noise and a small indentation...
Now I know what I'll need, yay!
Why does Ikea not put any drainage holes in most of it's stuff? Even if you use a second pot inside, you end up with icky-smelling water and mold and yuckness inside the outer pot... it rains outside, you know.