3D Printed Self-Watering Planter

by JON-A-TRON

31K42020

Intro: 3D Printed Self-Watering Planter

Avoid the danger of over or under-watering your plants with this self-watering planter. With a 3D printer, you can quickly make an attractive water-tight planter pot that will keep your plants healthy and fit in with your modernist aesthetic.

STEP 1: Design

I looked around online at self-watering planters and came up with the design you see here. Basically, it consists of a basin that keeps standing water and a cup with a perforated bottom that stays submerged in the water. The water in the basin wicks into the potting soil keeping it moist without drowning the plant. From what I gather, roots need water but they can’t be submerged in it for too long or the plant will die. The other danger with over-watering (I’ve heard) is that it can help propagate mold and fungus, which can also kill the plant.

In my design, I created a sphere with two circular cutouts in it. A larger one holds the planter cup that snugly fits a 3” plant, and a smaller cutout is for a spout that keeps water from spilling everywhere when you fill the pot.

I designed this pot in Fusion 360 because it’s easy to create complex geometry with it and it’s a breeze for 3D printing. I printed this on a Dremel 3D Idea Builder. The Dremel file and the STLs are attached here if you want to print your own.

Fusion 360 is free for students and hobbyists, and there's a ton of educational support on it. If you want to learn to 3D model the kind of work I do, I think this is the best choice on the market. Click the links below to sign up:

Student/Educator

Hobbyist/Startup

STEP 2: Assembly

I won’t get into the ins-and-outs of 3D printing here. If you need an intro, check out this instructable. The important thing is that the print is set to “solid infill”. You want a solid piece because any gaps in the infill will most likely cause the pot to leak.

Once the parts are printed, just insert the planter cup and the spout.

STEP 3: Plant

I’m not sure if it was necessary, but I added some pumice gravel to the bottom of the cup. I figured that if the water stays about on level with the top of the gravel, the soil at the bottom of the pot won’t be flooded, but rather will just wick up the right amount of moisture.

With the gravel in, I just placed the root ball into the cup on top of it.

STEP 4: Done

That’s it! I talked to the folks at the nursery, and they seemed to think it was a good idea. They said that with the right kind of plant (the thirsty kind), a constant low level of moisture in the soil should keep it healthy for a long time. If you’re like me, you tend to kill plants- hopefully this pot will save me (and my plants) from myself.

18 Comments

emorning 8 years ago

Very nice design.

I grow some of my house plants in a pot similar to this (actually, just a regular pot and a deep plastic saucer underneath) using nothing but perlite and vermiculite (3 parts perlite, 1 part vermiculite). No soil, the plants get all the nutrients they need from the fertilizer I add to the water. My plants seem to prefer it to soil, I think it's because the roots can always get all the oxygen they want. I did take the time to figure out how much vinegar to add to my watering can to make sure the pH of my water is right around 6, that makes a difference.

JON-A-TRON 8 years ago

Oh wow, I should give that a try. The fern I planted in this pot is now dead, and I'm not sure what I did wrong. The soil is moist, not flooded, but maybe that's still too much water. What kind of fertilizer do you use? What kind of plants?

emorning 8 years ago

I just use Miracle Grow. I use half the recommended amount because I think I've killed plants by using too much. I have a couple of different types of pothos, a fiddle leaf fig, a Z plant, and some succulents in perlite. All easy to grow plants. All at least 6 months old. All very happy.

These plants are in pots filled with perlite and vermiculite mixture. Underneath each pot is a plastic saucer that is 4 inches deep and a couple of inches wider than the pot. So in principle I think my pots work like yours, a reservoir of water wicks up to the 'soil' in the pot. I water often, every few days. I just water through the top of the pot until the saucer is almost full. I pay no attention to how wet or dry the perlite is, I just water until the saucer is full. I give no thought to when I last watered a plant.

I tried perlite because I read on the Internet that you don't have to worry about over watering because so much oxygen can permeate through the perlite to the roots. Root rot isn't caused by too much water, its caused by lack of oxygen. Soil is much more compact than perlite so it doesn't allow nearly as much oxygen to get to the roots, especially when it's wet.

Also, about a year ago I moved into a new house in a different town. I bought some new plants and they were very unhappy, a couple died. Then I read about the importance of pH to plants. If pH is too wrong then plants cant absorb nutrients. I bought a pH testing kit (cheap) and discovered that the water in my town is very alkaline (pH over 9). Using the pH kit I figured out how much acid I need to add to the water to get pH around 6 (where plants like it). pH seems to be a big deal, this made a big difference.

Anyway, based on my experience I'm sure your pot should work just fine for me. I have a homemade RepRap Prusa. I'll even get a fern for this :-).

sos13 8 years ago

I would love to print this and try it out. I had a dollhouse picnic bench printed in wood pla-we had a flood and the bench turned to mush. So I am curious. I can not download the bowl stl - it comes up as a htm instead of a stl. Can you help?

JON-A-TRON 8 years ago

.htm huh? Maybe try right-clicking on the title of the STL and "download linked file". That works for me...

flightOfTheNirdMan 8 years ago

What material did you use to print? I worry PLA will break down in water and ABS may be toxic for the plant.

JON-A-TRON 8 years ago

It's PLA. It's been full for about 2 months now, no leaks so far. Let's see how long it holds up!

HopMan3000 8 years ago

yeah i thought about the PLA braking down but it needs to be in at least 122˙ F

mchau2 8 years ago

simple and effective i think! good one... a thought about cleaning it... how frequent do you pour everthing out and clean it? cause hong kong is known for mosquitos problems!

JON-A-TRON 8 years ago

Good point! I've lived in California for more than 10 years, but I grew up in Louisiana, so I know that stagnant water is a very bad idea in some climates. I would imagine that if you also made a cap for the spout to keep mosquitos from flying into the pot and laying eggs, you wouldn't have to worry about it.

mchau2 8 years ago

thx for your understanding and the tip! cheers!

HopMan3000 8 years ago

I have a 3D printer (XYZ da Vinci Jr. 1.0, and it is not so junior - it is like a pro) I think this is a really ingenious design i will probably print it - if my Mac will let me download the files - on the bright side I'm a tech dude

gmendez3 8 years ago

I loved it! Master design!

randofo 8 years ago

As someone who habitually kills plants - I solute you.