Hands-On STEM Curricula: Make a Portable, Indoor Water Garden for $0-10

About a month ago, I went to Lowe's, looking for an inexpensive solar-powered pond pump to share with children at the Richmond Virginia BookLover's Festival. Unfortunately, there was no such item on the shelves, and Garden and Lawn staff told me they'd never seen it in stock. (You'd think solar pumps would be easy to find in home improvement stores, since they are available for as little as $9 on Amazon and don't require an exterior power source.)

I am a master of TMI, and, when I told one of the employees why I was looking for the solar-powered pump, he directed me to about 15 little plastic containers housing water lilies that he just put on the sale shelf for $1.00 a piece, a >85% markdown. Given that I am also a master of synergy-driven impulse, I bought every container, knowing I'd get them in children's homes or classes one way or another.

I'd planned on using the lilies to make water gardens with the Wednesday morning gardening club I oversee at my local elementary school. I don't have a budget, and I am generally determined to recycle materials whenever possible, so I asked the school listserve to bring to the school any large, clear plastic containers they come upon (i.e., Costco's huge Snyder's Pretzel or Cheetos containers are perfect). Despite the fact that Costco is within a mile of my house and parents are always providing large-quantity snacks to their kids' classrooms, it wasn't as easy to get 10 large plastic containers as I thought. Even after I emailed my neighborhood listserve, I've only been able to accumulate 6 containers (and counting).

Plan B has been to make water gardens at home with whatever big, clear plastic containers I can accumulate and give these to teachers at the elementary school. So far I have provided 2 water gardens to teachers, 1 water garden to our crosswalk guard, and 1 water garden to an 8YO friend.

Two more teachers requested water gardens for their classrooms this week. I thought I'd take photos while I make them, so teachers, homeschoolers (aren't we all?), and kids of all ages can see how easy (and inexpensive) it is to do.

1) To make it easier to peel off the labels, I soaked the pretzel containers for >2 hours in a sink of warm water containing a tablespoon of natural dishwashing liquid.

Tweezers or a straight-edge razor are better than fingernails for pulling off hard-stuck labels.

2) Next, you fill the container(s) with rain water, thereby turning it into a rain garden (a 'best stormwater management practice (BMP)' that filters stormwater using water-hardy vegetation). I have a little pond in my backyard, so I just get the water from there, but you could just as easily set out a bucket before the next big rain and use the water collected therein. You could also go to a nearby creek, stream, river, lake, etc., and fill your container there. I highly encourage you to use naturally occurring rain water because this brings the water cycle, weather, and natural filtration to the lesson.

You can also use water collected by a humidifier or air-conditioner, as this water was condensed from the atmosphere and does not contain the hazardous chemicals in tap water.

If you must, you can use tap water; but, if you are going to incorporate fish into your water garden (which I also highly recommend), be sure to treat it with a store-bought solution that eliminates chlorine, ammonia, and other chemicals in tap water that are dangerous to fish (not sure why we're drinking it if it kills fish that swim in it, but that's a lesson for another day).

3) Next you add your plants, in my case the $1 lily bulbs I bought at Lowe's.

Note: You don't have to buy pre-packaged water lilies. You can add any water-tolerant plant to your water garden: loriope, monkey grass, English Ivy, Creeping Jenny, just about any kind of lily, and even strawberries - as long as you keep the roots in the water and the leaves above it. It's also fun to use the hyacinth bulbs that seem to appear everywhere around Easter time.

4) You can stop here, place your budding water garden in a sunlit indoor location, and watch it grow, or....

5) You can add fish!

I keep guppies in my pond during the summer months, so they can eat mosquito and other larvae as well as beautify. I don't feed the guppies at all during the summer, and they breed like rabbits. At the end of the summer, I bring the ones I can catch inside and feed them store-bought fish food (see photo above) and/or fatty insects (moths, flies, etc.) that turn up in the house. These fish have live birth, so it's a lot of fun to watch the females get super fat and a flurry of tiny fish appear when you least expect them.

(Note: Most people purchase the flamboyant fighting Beta fish, which must generally live alone due to its aggressiveness. I think guppies are better because they are 1) smaller and content with close quarters (because they are schooling fish); 2) less expensive (if you buy a male and a female, your future guppies are free!); and 3) easy to maintain (you don't even need artificial light or a filter if live plants are in the water).

If your vegetation grows well, there should be no need to clean your water garden, because plants naturally filter out the nitrogen (ammonia), phosphorous and other hazardous chemicals in accumulated fish poop. However, due to evaporation alone, you will need to replenish the water from time to time. Do not replace more than 1/2 of the water at a time (this can shock the fish and kill them). Again, you can replace the water with rain water collected in a bucket or from a stream/creek/waterway, or you can use tap water that has been treated with store-bought solution that makes it safe for fish (see above).

Since we adopted our big kitten, Kale, we have discovered yet more benefits from our indoor water garden. Kale *loves* to drink from it, and the fish provide him occasional (and much needed) entertainment. (Note: It is generally agreed that cats can safely drink fresh (non-stagnant) rain water and, in fact, prefer it to tap water. Just be sure that the plants you use aren't poisonous to cats.)

A few final notes:

1) Do not start with more than 3 guppies (other fish, except for a single Beta, will become too large); and do not start with only one (they are social fish). If you don't want to end up with a serious ecosystem lesson on your hands (i.e., 100 guppies by winter's end), you should get guppies of the same sex. The males are the flamboyant ones (of course), their Chinese-dragon fins fanning out behind them. The females just have a crescent moon of colors on the ends of their tail fins.

That said, breeding guppies is SUPER fun, and a good number of them in the pet stores are doomed to become fish food, so you may actually be buying their genetic line a little time. If you choose to buy guppies of different sexes and take the ecosystem lesson route, just remember that, unless you have an aquarium or a pond that can extend their lives one more summer, you're going to end up with an overpopulation of guppies on your hands. In other words, be prepared to clean out dead fish (or thin out live ones) and change the water daily. (Of course, this could be a gentle way to introduce your child to the concept of death, which is better done sooner than later, as Death does not discriminate.)

2) Do not overfeed your fish. You only need to put a couple large flakes of fish food in the tank every *other* day. Be sure to remove any food left uneaten after 5-10 minutes, as accumulated left-overs can contaminate the water with more nutrients than the plants can absorb.

3) Be sure to remove dead leaves from the plant/water, so that they don't overcome your water ecosystem with nutrients (from decay) that can kill the fish and eventually even the plants inside. You should also change (not more than 1/2) of the water if it gets really cloudy.

4) Be sure not to overcrowd your water garden with plants/roots. Even guppies need adequate space to swim and be happy (they will die if they don't keep water moving through their gills). If the plants start to overtake your container, simply remove and discard the crowders or place them in another water pot, one with enough space for them to really spread their leaves :-)

5) As your water lily gets bigger (it can grow quite rapidly), you can move it (and the fish if you like) to a larger, perhaps more decorative pot (thrift and consignment shops often have appropriate large containers for a few dollars). In early summer, place your water garden outside, so your plant can soak up direct, natural sunlight and your fish can naturally eliminate mosquitos and other blood-sucking insects in your yard.

6) Most Importantly, HAVE FUN!!

Note: There are heaps of varieties of lilies, so you can choose just about any combination of colors and styles for your water garden. Here's a great resource for making your selection(s): https://happydiyhome.com/lily-varieties/.

My blog contains a number of other engaging and practical lesson plans. I hope you'll check them out!

http://www.melissarooneywriting.com/blog/?s=lesson+plans