Expandable Mason Jar Greenhouse





Introduction: Expandable Mason Jar Greenhouse

About: I like plants. Also an aerospace engineering student.

I recently got into simple passive hydroponics and I've been growing some various plants in my dorm room for a month or two now. Currently I'm using a box covered with plastic wrap to house several plants. However, I quickly realized that the plants I'm growing will soon outgrow the maximum height of the box. To remedy this, decided to create a modular, 3D printable system that screws onto a wide mouth mason jar allowing for plants to grow freely vertically.

Step 1: Step 1: What You Need

For this project, you'll need:

- a 3D printer

- Thumbtacks

- Plastic Wrap

- A pint sized, wide mouth mason jar

- A netting cup and some growing media (if you want to do hydroponics)

- Scissors

- A plant for the planter!

Step 2: Step 1: Printing All the Parts

To start, print out the following:

1x "base v1.stl"

6x "leg v1.stl"

1x "modular expansion v2.stl"

1x "top v1.stl"

You will need to turn on supports for "base v1.stl" but the other parts should be able to print without supports. I printed these on a Monoprice Maker Select v2 with 0.2mm layer height. If you want to print out additional vertical expansions, make sure to print 6 legs for each expansion that you print.

Step 3: Step 3: Connecting the Legs to the Vertical Expansion

In the interest of strength, I decided to design the legs as separate pieces from the vertical expansion. The downside to this is that you have to attach them to the vertical expansion. After removing any brim/raft the legs were printed with, insert the square end into the square holes on the vertical expansion piece. I designed these to be a friction fit and used tolerances that work well for my printer, so depending on your printer you may need to sand down the edges of the legs a bit.

Step 4: Step 4: Assembling the Frame

After interfacing the legs with the vertical expansion ring, connect the ring to the base part. This is also a friction fit, so you may need to do some sanding. Connect additional expansion rings in the same manner. After assembling the frame, screw it onto the mason jar.

Step 5: Step 5: Plastic Wrap

Add the lid to the frame. Then, take a large sheet of plastic wrap and some thumbtacks and start wrapping the outside of the frame with plastic wrap, using the thumbtacks to keep the plastic wrap in place. I designed the frame with holes in various places to accept the thumbtacks, as shown in the picture. Use scissors to trim away excess plastic. When wrapping the top of the frame, make sure to poke a few holes so that the plant has sufficient air. If your thumbtacks are too loose, add some super glue or hot glue to help them stay in place. Also, make sure to cut off any part of the thumbtack that sticks out of the frame, so as not to injure yourself.

Step 6: Step 6: Adding the Plant!

Now that the frame is assembled, all that's left to do is add the plant! Separate the frame from the mason jar and drop in your plant of choice. This frame is intended to work for both a Kratky hydroponics system or traditional soil planting, so choose whichever you prefer. As your plant grows, print additional vertical expansion rings and legs to allow it to continue to grow freely!

Step 7: Conclusion

I hope you enjoyed this Instructable! This was my first time making one and I was definitely pretty rushed to complete the project in time to enter the Planter Contest, but it was a fun time nonetheless. Please feel free to message me if you have any suggestions, criticisms, or comments on the planter!



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    4 Discussions

    would it be better to print the part that attaches to the jar upside-down? then you would only have support material for the centre and not the full outside. this would reduce the amount of wasted material? just a suggestion.

    1 reply

    Ah dang that's a great idea. I was thinking about the orientation all wrong, but I think you're right. Such a simple yet effective fix. Thanks for the tip!