Growing a Venus Fly Trap Indoors in a Dry Environment
Intro: Growing a Venus Fly Trap Indoors in a Dry Environment
I've been interested in carnivorous plants since I was a kid, but I haven't had any for about a decade. Recently, though, the idea of growing a venus fly trap in my dorm room hit me. There were a few issues I had to overcome before growing one, though. There are three major environmental factors venus fly traps require: high humidity, lots of light, and a nutrient-poor soil watered with distilled water. The soil is an easy problem to solve. Humidity is a bit trickier, but even in a place a mile above sea level as long as the terrarium has relatively small openings for air the humidity stays high enough inside. Light is another big issue. I don't a whole lot of sunlight through my window, so I integrated an LED light source into the terrarium. I have it running on a timer 10 hours a day, so between this and the sunlight I think it's getting the rough equivalent of a day of direct sunlight.
STEP 1: Design
I designed 6 interlocking panels in SolidWorks that together comprise my terrarium design. My design calls for the sides to be laser-cut from 1/4" acrylic. The interlocking design gives it a cool look, makes it a lot easier to glue the terrarium in the right shape, and gives it a better seal when complete.
STEP 2: Laser Cutting
I used a 100-watt Epilog laser cutter my college has to cut the panels from 1/4" acrylic. The design was intricate enough that any other cutting method would take longer and not give as nice results. Using the laser cutter, the panels came out with very clean, accurate lines. This made the final terrarium look very nice and helped the pieces interlock correctly when I glued them together.
STEP 3: LED Light Source
In the solid model design of the terrarium, I designed a 5X5 grid of 5mm holes in the top panel. I bought a bunch of white LEDs off eBay and glued 25 of these into the holes. By folding the leads of the LEDs down and soldering them together, I wired all of the LEDs in parallel. I wired up this circuit to a 5V phone charger I had around. It would be good engineering practice to wire these LEDs in series with the LED circuit to drop the voltage across the LEDs, but because there are so many LEDs they can handle this kind of voltage without burning out. I plugged the power supply into a timer so it automatically runs for 10 hours a day, hopefully giving the venus fly trap enough light.
STEP 4: Assembly
To assembly the terrarium I glued the panels together with Devcon Weld-it. It is a waterproof, flexible glue that dries clear, bonds plastic, and dries quickly. The catch is that it's super toxic, highly flammable, and emits a lot of nasty volatiles when drying, so I had to be really careful using it. With the interlocking design of the panels, I had to be aware of which surfaces would be contacting when glued, and make sure to spread glue on all of them. I glued two side joints at a time, then glued the bottom on. I taped it together to ensure that it would dry in the right shape overnight. I then ran a bead of glue along each inside seam. Even after all this, there were still one or two leaks, but I was able to seal them easily enough with a drop of glue. After a few days of containing moist soil, there don't seem to be any leaks, so the terrarium seems waterproof.
STEP 5: Getting the Venus Fly Trap
Believe it or not, you can buy venus fly traps online. I've bought two of them this way, and they seem to survive the shipping process pretty well. The two websites I've used are:
http://www.predatoryplants.com
and
http://www.flytrapshop.com
The plants from Predatory Plants seem to be a bit healthier and older, but the Fly Trap Shop has a bigger variety, so it's a trade-off. The one I got for this particular project was from the Fly Trap Shop because they were the only ones with the Akai Ryu cultivar in stock. I didn't know this until I started researching venus fly traps recently, but there are a lot of different breeds available (when referring to plants, they like to call them cultivars). The Akai Ryu (red dragon) cultivar, shown below, is red rather than the traditional green. In the pictures, you can see that mine is green, hopefully because it's still young and not because they sent me the wrong kind.
http://www.predatoryplants.com
and
http://www.flytrapshop.com
The plants from Predatory Plants seem to be a bit healthier and older, but the Fly Trap Shop has a bigger variety, so it's a trade-off. The one I got for this particular project was from the Fly Trap Shop because they were the only ones with the Akai Ryu cultivar in stock. I didn't know this until I started researching venus fly traps recently, but there are a lot of different breeds available (when referring to plants, they like to call them cultivars). The Akai Ryu (red dragon) cultivar, shown below, is red rather than the traditional green. In the pictures, you can see that mine is green, hopefully because it's still young and not because they sent me the wrong kind.
STEP 6: Planting
Venus fly traps require some very specific planting conditions. They need soil that has zero nutrients; they're evolved to live in a nutrient-poor environment and derive nutrients from the insects they eat. They also need to be watered with distilled water, as the nutrients in tap water build up over time and can be hazardous. I suspect that purified bottled water (not spring) will work as well, but I've only ever used the distilled water you can by in gallon jugs at grocery stores. I took a mixture of 1/2 peat soil and 1/2 pearlite, soaked it in distilled water in a ziploc bag, and spread out a layer in the bottom of the terrarium about an inch and a half thick. I made a hole to the bottom and
22 Comments
AlexS267 8 years ago
May I know the wat to create poor nutrient soil watered with distilled water?
Venus fly trap need soil with poor nutrient soil to grow in amI right to say that?
Does any soil without nutrients works?
MichaelB735 7 years ago
The reason for the poor (ideally "no") nutrient soil is that Venus Fly Traps evolved to absorb their nutrients through flies and other small insects; their roots do not serve any real purpose other than anchoring them in the soil. If you served the plants nutrients or minerals in the soil, they will not be healthy, and could even die, because it is too much for them to handle.
bigerboy654 8 years ago
mseba 12 years ago
mrmerino 12 years ago
mseba 12 years ago
SIRJAMES09 12 years ago
Having said that, people need to realize that this is YOUR instructable, & in this blog, you are going to do things YOUR way. It's ok to disagree, but do it in a respectful manner.
Now for my opinion.
I Love it!!! :) I think the box is like majorly cool looking!!! It's just a wee bit beyond my skills to make one, but I still think it's cool!
I have seen different jars & & other glass containers in places like Jo Ann Fabric & Crafts, and I just wonder if they might work for this....I love terrirriums and have several store bought ones that I either bought or received as a gift....plants like this have always fascinated me but I never knew where to get them or how to keep them alive.
TY Sir for sharing this, this has given me a place to start research on these kinds of plants.
Biotele 12 years ago
skrubol 12 years ago
Madrigorne 12 years ago
formellini 12 years ago
Vlorbschnat 12 years ago
formellini 12 years ago
is not a dog and you don't have to feed it.
use only distilled water and leave it outside iven if is snowing or freezing.
Madrigorne 12 years ago
ac-dc 12 years ago
You may have been lucky, generally speaking it is not true that a person can expect to wire LEDs like this and have them survive. Further, how long have they been running? They may have very short lifespan and quickly reduced efficiency if the LED die runs too hot.
Generally speaking one should never run an LED without current limiting in the drive circuit. That can be a purpose designed switching driver or with budget/simple implementations, more often a series resistor to limit current.
However, a 5V source is fairly poor for white LEDs due to them having a forward voltage around 3.2V. This means you have to drop a large %, 1.8V input which creates heat and wastes some power. It would be better to use a regulated 12V switching wall wart like those often supplied with consumer electronics, then wire parallel strands of 3 LED in series. Next consult the datasheet for the forward drop of the type of LED you use (3.2V mentioned above was only a ballpark # for this size) and plug these numbers into an LED calculator (found via web search engine) to determine the ohms resistance and wattage of resistor needed for each parallel series of 3 LEDs.
With the number of LEDs (and their being 5mm type) it is very unlikely you are giving them the equivalent of a full day worth of sun. Supposing roughly 2 lumens per LED x 25, 50 lumens of light (this would be at ideal drive current which we haven't established as mentioned above), it is only a small fraction of what the plant would receive if it had direct sunlight in a good location. However, only giving it enough light to survive works too! If it thrives too well you'll outgrow the terrarium too soon.
tsinnock 12 years ago
lance.plater1 12 years ago
lizardknits 12 years ago
em21701 12 years ago
rhilderbrand 12 years ago