How to Set Up Your Grow Kits
1. Set up and level the redwood plant bench. Start by screwing the thumbscrews into the threaded inserts on the bottom of the redwood plant bench. Placing a few drops or spraying some oil into the inserts will make it easier to screw in the thumbscrews and protect the inserts from moisture.
Next, set the redwood plant bench where you want it and then level it by setting one or two plant trays on the redwood plant bench and then setting the level on the plant tray(s). We level it lengthwise and then on each side. Looking down, if you turn a thumbscrew clockwise, your bench will get taller. Take your time, it’s important to get the bubble right in the middle.
Tips for DIYers – Making Your Own Plant Bench
To accommodate the plant trays, the distance between the rails of the plant bench should be 4 9/16”. You will need to drill 9mm holes for the threaded inserts that come in our DIY kit. The holes should be at least 1 ¼” deep. You will also require a 6mm hex key to screw in the inserts. The rails should be at least 2 ½” high and a minimum of 5/8” wide. The base supports, around four, can be made from the same piece of wood as the rails and should be a minimum of 5/8” high. The wood should be dry, or it may warp as it dries out.
2. Assemble the water control valve and position it in the control valve house. Take off the lid, open the small baggie, and take out the two silicone stoppers. Insert one stopper into the front recess of the bottom float and the other into the recess on the underside of the top float. Use clean, dry hands for this part because it’s a close fit.
Next, attach the bottom float to the main body. With both the main body and the bottom float belly-up, insert one of the posts on the bottom float through the cut-out on the main body, and then click the other post into place. Set the top float and caps aside until the last step.
Now, push the top hat grommet into the hole on the front of the control valve house and then push (and pull) 6” or so of the long piece (3’) of ¼” tubing through the grommet. The tubing slides through the grommet easier If you first wet it in a glass of water. Also, a pair of thin, grippy gloves are helpful. Slide the 1/4” clamp over the end of the tubing (short end), and then slide the tubing over the nozzle of the main body. Align the nozzle square with the tubing and then wiggle the tubing onto the nozzle.
Position the clamp all the way up against the main body and then close the clamp with a pair of pliers to close the clamp tightly. Now, very slowly, pull the tubing back through the grommet until the main body is up against the small posts that protrude from the floor of the control valve house. Be careful, as pulling too fast can pull the grommet out of the hole. Also, don’t let the front of the main body go over the posts. Finally, push the c-shaped recess at the back of the main body into the T-shaped post at the back of the valve house. Give the tubing a slight tug to ensure there’s tension holding it in place.
3. Connect the tubing to the plant trays. First, slide the two short pieces of ½” tubing onto the fittings on the underside of the control valve house. Next, slide a black rubber cap onto one fitting of a plant tray. To the opposite fitting, attach a long piece of ½” tubing. Continue attaching tubing to fittings until you’re out of tubing, then connect the end fitting to the short piece of ½” tubing at the back of the control valve house where there is no grommet hole.
Tip: Each piece of tubing has a curve from being in a roll. The plant trays will sit flatter on the redwood plant bench if you connect the tubing so that the curve is up.
4. Connect the reservoir. Insert the reservoir top hat grommet through the hole in the reservoir. To make this work, wet the tubing and fitting, line the tubing up square with the fitting, and push it in until you feel it grab. Connect the short (6”) piece of ¼” tubing to the ¼” shut-off valve. Push the other end of the ¼” tubing through the reservoir top hat grommet. Run the long (3’) piece of ¼” tubing from the control valve house underneath the end plant tray (on the reservoir side of the plant tray) and connect it to the other end of the ¼” shut-off valve. Cut off excess tubing with a pair of scissors.
Tips for DIYers - Working with the Reservoir & Grommet
You will need to drill a 3/8“ hole near the base of your reservoir to accommodate the ¼” top hat grommet. If you have a lid that seals, you should drill a ¼” hole near the top of the reservoir. It’s very unlikely for mosquitos to fly into a hole that small.
5. Attach the top float to the main body by holding the top float vertical (cylinders at the top), slide one of the posts on the top float through the open-ended post on the main body, and then slide the top float back so that the other post on the top float goes through the hole of the other post on the main body. Place a cap over each cylinder.
Testing Your Grow Kits
1. Wet the system – First, wet the entire system by first placing a wick into each plant tray and then pouring water into the control valve house until the water level nears the top of each plant tray.
2. Fill the reservoir - The system should still be full of water from the prior (wetting) step, so drain it by pulling one of the end caps. Let the water drain out until the water level is below the floor of the valve box. Next, fill the system with water from the reservoir by filling it with the reservoir shut-off valve closed and then opening the shut-off valve. When the water level is near the top of each plant tray, the water control valve will shut off the flow. If water is overflowing, then recheck that the redwood plant bench is level.
3. Connect the plants - Place a square of the capillary mat (light-colored fabric) over the wick on each plant tray. Put a square of landscape fabric (dark-colored fabric) on top of the capillary mat. Wet the squares of the capillary mat and landscape fabric first by dipping them in water. Next, position the potted plant on top of the landscape fabric so that as many of the holes in the bottom of the pot as possible are in contact with the fabric.
Planting Tips - Potting Mix & More
We recommend using the original MiracleGro Potting Mix – not the water retention version. Fill the pot up even to the top, and then press it down about an inch or so until it’s firm enough that digging a hole won’t cause a cave-in. Now, you can press in the transplant and place the pot on a plant tray. Hand water it from the top with about a ½ liter of water. That should do it, but keep an eye on your plants for a few days to make sure that the wicking is working. If the plants start to dry out, continue giving them a shot of water from the top until the capillary action kicks in. You can also place bark mulch on top of the soil to reduce evaporation.
Tips for DIYers – Selecting Pots
Keep in mind that capillary action in most potting mixes is limited to around 7” in height. Because of these height limits, the ideal pot size is between 6” to 10” in diameter at the top of the pot. Make sure your pots are not much more than 9” in height.
Although this system is intended for herbs and flowers, many larger plants will still thrive as long as they have an additional means of support. They’ll need to grow around a stick or trellis, as their roots won’t grow deep enough to sufficiently anchor the plant.
Also, the drain holes at the bottom of the pot must be in contact with the landscape fabric. Depending on the configuration of the drain holes, additional holes may be needed. If there is a gap between the landscape fabric and the bottom of the pot, then you will need to use a slightly longer wick. Use a box cutter to cut the wick and scissors to cut the tubing.
There are many variations to the grow kit configuration, depending on your garden set-up and plant needs. Here are some tips to address a couple more details.
Some pots may come from the nursery with small drain holes or in potting soil that makes it difficult to get capillary action started. For these, hand water the plants from above for a week or so. As the water drains through the bottom holes, it will deposit small particles of soil on the fabric landscape mat and help establish capillary action. After a week, when you open the reservoir shut-off valve, the capillary action should start right up.
There is minimal maintenance for our grow kits, but you must ensure there is adequate water in the reservoir at all times. The water level in the reservoir needs to be a minimum of several inches above the control valve house. If your reservoir is allowed to dry out, you will need to rewet the soil from above. A dry soil medium will tend to repel water rather than absorb it, so the capillary connections will need to be re-established.