Field Manual

CWI Classic

How the CWI Classic works

The CWI Classic reservoir is filled by hand every 2-3 weeks, depending upon the plant type and location. The reservoir fill hole is plugged with a stopper, creating a closed reservoir.

The water in the reservoir flows into the soil through tiny holes at the bottom of the CWI Classic. The water wicks its way up through the soil until it reaches the moisture sensor, planted 1/3-way down the container. The sensor tip absorbs water, and closes like a valve, preventing air from passing through the tube into the reservoir.

A vacuum develops above the reservoir, preventing water from saturating the soil. As the plant uses the moisture and the soil starts to dry, the sensor tip dries and allows air to pass through. The vacuum is broken, allowing water to flow into the container, until the soil becomes moist again.

The process forms a cycle, interrupted only by the removal of the stopper and the filling of the reservoir. The overflow drainage adapter at the bottom allows excess water that builds up (typically rainwater) to escape without disrupting the system.

Bioguard

Planter Technology recommends the use of Bioguard fabric (sold separately) to prevent the growth of roots into the water reservoir. One Bioguard square is placed (either side up) into each "cup" at the base of the CWI Classic. Cut a hole in the center of Bioguard squares used in the CWC-1500 and 1800 to accommodate the overflow drainage adapter. Use gloves when handling Bioguard, and observe precautions on package.

Overflow Drainage Adapter

The riser extending up from the bottom of the planter is the exterior drainage adapter. Care should be taken when planting not to bend or break this pipe when planting. Do not remove the factory-fitted screen of soil-separator fabric prior to planting. The adapter allows excess water to overflow after heavy rains, but prevents soil from washing out. For use of CWI Classic indoors, thread riser out of base, and replace with a _" MNPT plug to prevent drainage.

Planting and Sensor Placement

Drape sensor over outer edge of container prior to planting. Firmly pack moist soilless potting mix into the "cup" at bottom (on top of Bioguard square), and across bottom of insert up to the level where the bottom of the plant’s rootball will sit. The crown of the primary plant’s rootball should be 1" below level of fill hole. Remove the plant from its’ nursery container, place into CWI Classic. Check to make sure white tip is at end of sensor tube. Place sensor tube down into the container at approximately a 45° angle towards center of planter. Sensor tip should be approx. 1/3 way down in the soil of the CWI Classic (see diagram). Pack additional soil around primary plant to bring soil up to the level of the underplantings, packing solidly to fill gaps and voids. Place underplantings around primary plant as required, and pack soil firmly in between.

Deeper sensor placement results in lower soil moisture content.

Filling and Maintenance

Prior to filling reservoir, check to insure that soil is well packed, and that sensor is placed correctly. Remove stopper, fill reservoir with clean water until full. Top water underplantings lightly during first week or two. The unit may weep a small amount of water for the first 12-24 hours after filling. CWI Classic will weep between fillings if excess water builds up after a rain, after heavy top watering, etc. Because removing the stopper breaks the internal vacuum and disrupts the system, remove stopper to check water level no more frequently than necessary -typically every week to two weeks. Refill unit before reservoir goes empty. After filling, moisten stopper and replace firmly in fill hole with a slight twist. Fertilize with Planter Technology HM-10 time-release fertilizer for sub-irrigation systems, or other water-soluble fertilizer. For other fertilizers, use _ the strength recommended by manufacturer.

Troubleshooting

The properly functioning CWI Classic will have dry topsoil, and will not weep after 12-24 hours. The soil 2"-4" below the surface will be moist, but not wet.

Signs of Overwatering (a more common problem): Topsoil is wet or damp to the touch, or the unit continues to weep after 24-36 hours. Removing the stopper to check water level more often than necessary may lead to overwatering. To fix, repack soil solidly, adding additional soil if necessary. Plant sensor slightly deeper, making sure that the sensor is firmly packed in soil. Check that stopper is securely in the fill hole. Allow soil to dry out until the topsoil is dry to the touch before refilling reservoir.

Signs of Underwatering (a less common occurrence): Reservoir level remains unchanged between fillings. Look for signs of water stress, and test moisture level at least 2" below topsoil for moisture (the plant may not have needed water). Remove stopper, watch approx. 3-5 min. to see if water level drops. If it does, system is functioning. Top water lightly. If level does not drop, top water plant and wait another week. Remove stopper again, observe water level. If water still does not drop, inlet holes at bottom of planter may be clogged, and will require removal of plant to open.

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