Ahhhh, summer. It’s when sun-loving people tend to spend more time outside taking in the fresh air. It’s also the perfect time to give the plants in your hydroponic system a break from the sheltered life they’ve been living indoors.
With a little preparation, growers can successfully employ hydroponics outdoors using a homemade hydro system, leaving the unrelenting duty of providing proper lighting and ventilation to Mother Nature, who supposedly knows best.
Indoor growers can make the move outdoors and achieve explosive growth using an inexpensive DIY hydroponics system, especially with a circulating bucket system. A circulating bucket system is relatively easy to build and maintain, and it will let you grow large, hearty plants that better withstand the elements and produce massive harvests.
BetterGrow Hydro Founder David Goldman recently assembled a circulating bucket system in his back yard and just harvested his first tomato, less than two months after transplanting into the system. Here’s what you’ll need to do the same in an easily expandable four-bucket system:
- One bag of Canna Coco - 50L
- Four 5-gallon Buckets
- Four 3.2-gallon Buckets
- One Standard Controller for Bucket Systems
- Four G.H. Farm Kits
- One WaterFarm 8-Pack Circulating Upgrade Kit
- One 1/2” Inline Shutoff Valve
- One Eco Air 4
- Twenty feet of Flexible Air Line Tubing
- One Dual Outlet Analog Timer
- pH Up and pH Down
- One gallon of Botanicare CNS 17 Bloom for Coco & Soil
- Hanna pH/EC/TDS/Temp Waterproof Pen
- Stealth-RO100 Reverse Osmosis System
- A power drill and pliers (if you don’t already have them)
From hydroton to rockwool, a variety of growing mediums can be used in a bucket system. But outdoors, where plants will demand at least twice as much water as indoors, growers may want to lean toward a medium that will hold more moisture than hydroton. For that reason, try Canna Coco.
Controller and reservoir
The 5-gallon buckets are connected to a Standard Controller for Bucket Systems, which includes a 13-gallon master reservoir and an 8-gallon controller module. The controller sits beneath the master reservoir and is connected to the master reservoir with a float valve. As plants feed from the buckets and the water level drops in the controller, the float valve triggers and refills the controller from the master reservoir, helping the controller maintain a constant supply of water and nutrients to the buckets.
Each 3.2-gallon bucket should be outfitted with a G.H. Farm Kit, which includes a support and pumping column that extends from the bottom of the 5-gallon bucket to the 3.2-gallon bucket, where it attaches to the drip ring. An air pump attaches to the pumping column and pushes highly oxygenated nutrient solution from the 5-gallon bucket up to the drip ring.
Use the WaterFarm 8-Pack Circulating Upgrade Kit to link the buckets to the controller, allowing the nutrient solution to circulate between the 5 gallon buckets and the controller. Circulating the nutrient solution ensures that the pH and TDS levels remain constant throughout the entire system, and it enables the grower to check these parameters directly from the drain level tube in the controller rather than checking each individual bucket, dramatically reducing the labor involved during the growing season.
To simplify mixing and adjusting the pH and TDS of fresh nutrient solution without letting it seep into the system before it reaches the desired ranges, you’ll also need a 1/2” Inline Shutoff Valve to install between the master reservoir and the controller.
Air pumps are the workhorse of the hydroponic bucket system. They pull double duty by oxygenating the nutrient solution and moving it through the pumping column to the drip ring, which irrigates the growing media. The Eco Air 4 pump has four outlets and is perfect for the pumping needs of four buckets. If you are using eight buckets, two Eco Air 4 pumps will suffice. Add an Eco Air 1 pump for each additional bucket in the system. Make sure to keep multiple feet of Flexible Air Line Tubing on hand to connect the air pumps to the buckets.
Putting it all together
The WaterFarm 8-Pack Circulating Upgrade Kit makes it easy to connect the buckets to the controller. It has all the grommets, straight and elbow barbed fittings, 1/2” blue tubing, recirculating pumping column and the 1/4” and 13/16” drill bits you’ll need.
- First, use pliers to remove the handles from the 3.2-gallon buckets.
- Position the drip ring in the center of the 3.2-gallon bucket and make a mark under the “T” in the drip ring. That is where you will drill the hole for the pumping and support columns, which will be about 1 inch from the side of the bucket. Using the 13/16” spade bit, drill the hole for the pumping column and support tube.
- Then, using the 1/4” bit, drill a series of equally spaced 1/4” holes (about 30) in a pattern that radiates from the center of the bottom of the 3.2-gallon buckets so the growing chamber will easily drain into the 5-gallon buckets.
- Use the 13/16” bit to drill holes on opposite sides of the 5-gallon buckets about 1 inch from the bottom, and insert a 1/2” grommet in each hole.
- On a level surface, space the 5-gallon buckets, controller module and master reservoir as desired and connect them in a loop using the 1/2” blue tubing in between each bucket.
- Assemble the float valve in the controller, and insert the 1/2” grommet and barbed “T” fitting, both of which come with upgrade kit, in the hole in the bottom of the controller.
- Install the 1/2” Shutoff Valve in the 1/2” tubing between the master reservoir and the controller. This will make it easy to mix the nutrient solution in the master reservoir without it seeping into the system before it is at the proper pH.
- Place the Eco Air 4 in a dry area near the buckets and, using the 1/4” Air Line Tubing, connect each outlet to the air tube protruding from the pumping column. Plug in the timer, plug the air pump into the timer and set the timer to irrigate twice a day for 15 minutes to start. Reduce or increase the irrigation cycle as needed to best suit the size of your plants and your growing environment. When using coco, you will probably need to irrigate between one and four times each day.
Fill ‘er up
Place the master reservoir on top of the controller, close the 1/2” Shutoff Valve and fill the master reservoir with water and check for leaks. Then, drain the system and close the shutoff valve before filling the master reservoir with nutrient solution at the desired pH and TDS. Open the shutoff valve until the nutrient solution empties into the controller module and fills the buckets. Close the shutoff valve, top off the master reservoir with nutrient solution and re-open the shutoff valve.Now it is time to transplant your plants into the 3.2-gallon buckets.
Without shade, outdoor plants will receive about 10,000 lumens per square foot. That’s roughly the equivalent of having a 1,000-watt High-Pressure Sodium lamp one foot away from each plant.
For plants that require close to 12 hours of darkness to begin flowering, don’t worry -- Mother Nature sets the timer for you when growing outdoors. The summer solstice, the longest day of the year, just passed on June 21 and delivered 15 hours of daylight. During July, the amount of daylight will gradually reduce from 15 to 13 hours a day, and on Sept. 23 the natural light cycle officially switches to 12 hours of light and 12 hours of darkness, an event known as the autumnal equinox.
From that day on, the number of daylight hours continues to dwindle, with 10 to 11 hours of daylight in mid-October, which is usually harvest time. The days then get progressively shorter until just nine hours of daylight reach the northern hemisphere on Dec. 22, the winter solstice.
Plants that you pick up from a nursery, where they’re already growing outdoors, should already be hearty enough to go directly into your outdoor hydroponics system. But if you plan on starting outdoors now with seedlings or other immature plants in their first few weeks of life indoors, know that full sunlight will be far too intense for them. Prep smaller plants indoors under T-5 Fluorescent or Metal Halide lamps for about a week. Then, introduce them to a shaded area, or create one using shade cloth. You can also introduce your plants to the sun by putting them in direct sunlight for one hour per day, gradually increasing the number of hours of direct sunlight per day over the course of a week or longer.
Outdoors, reservoir temperatures are going to rise with the ambient air temperatures. That’s not a problem if you‘re growing warm-season plants like peppers and tomatoes, which don’t mind a little heat and will actually perform far better if irrigated with warmer nutrient solution.But if you’re growing less heat-tolerant plants in the summer heat, you may want to find a shady spot for your master reservoir and controller. That will help knock a few degrees off the temperature of the nutrient solution and maximize the amount of dissolved oxygen that reaches the root zone.Make sure that electrical items you are using -- power strips, air pumps and timers -- are protected from rain and sprinklers when they are outside. This can be as simple as putting them in a small, sealable plastic container with holes to accommodate the cords, or by covering them with a plastic bag and hanging them a few feet above ground.
Your outdoor hydroponic garden can quickly turn into a veritable buffet for pests, so it will need a little protection. As a preventative, start with a full-cover spray using SaferGro Pest Out Miticide or any neem oil- or pyrethrum-based pesticide -- all of which are organic -- and use Coco Wet as a sticker-spreader in a spray bottle to tamp down spider mites, thrips and aphids.
Caterpillars are especially fond of tomato and many other plants. To get the upper hand before they do, use 1 teaspoon (5 ml) Safer Caterpillar Killer with 1 ml Coco Wet per quart of spray mix. For best results, use the spray on caterpillars while they are still young.
Feeding the plants’ needs
If you are already growing plants hydroponically, your nutrients will probably work well in your new backyard hydro system, especially if you’ve been growing indoors in coco. But if you are not using Botanicare’s CNS 17 for Coco and Soil, which is specifically formulated to balance coco’s high nutrient absorption capability, you may want to pick some up to fully realize the benefits of using coco as a growing medium.
For best results, use a Stealth-RO100 Reverse Osmosis System. It produces 100 gallons per day of low-TDS water free of the chlorine, chloramines and salts that kill beneficial bacteria. That’s a good thing, because Canna Coco comes pre-charged with beneficial trichoderma.
An RO filter will also greatly reduce the amount of calcium and other tap water impurities that accumulate in the system, as well as the amount of flushing necessary to counter that buildup.
With all this in mind, it’s time to get to BetterGrow Hydro, either in person or online, because you’re burning daylight.