Use your hose bib to attach devices that will save you money and time: a water meter that shuts off the watering system automatically, or a fertilizer injector that mixes fertilizer with water in the hose.
Water Meters and Timers
One type of water meter measures the flow of water passing through and shuts off after a pre-set amount. Another is a simple timer, turning the water off after a pre-set time. Both types have a bypass setting, allowing you to use the timer as a faucet; this avoids the problem of taking the meter off and on to use the faucet for other purposes.
These very useful devices allow you to set the sprinkler going, and then ignore it. They are handy for people who forget their water for hours, or people who would like to leave the house without coming home to turn the sprinkler off.
A timer turns your water on and off. These simple, battery-operated controllers can be programmed to turn on and off at any time of the day. They are much less expensive than controllers used with underground sprinkler systems, need no wiring, and are attached to a faucet. This type of timer is often used with drip irrigation systems, but work with hose-end sprinklers, too.
Fertilizer Injectors
Fertilizer injectors feed a measured amount of liquid fertilizer into an irrigation line so you can feed as you water. They are extensively used in greenhouses and sometimes in nurseries. Most, however, are too expensive for home use.
One simple type has a venturi valve built in. This valve is simply a constriction in the throat of the device that causes a slight suction. This suction is used to draw fertilizer solution into the hose. It has no moving parts and is inexpensive enough for home gardeners.
Usually made of brass, it proportions liquid or soluble fertilizer into the water that flows through the hose. One end has a female fitting to screw onto the hose bib; the other end has a male fitting to accept the garden hose. A small rubber hose runs from a short brass nipple extending from the bottom of the injector to a bucket of fertilizer mixed with water. Water passing through the injector draws the liquid fertilizer from the bucket by forming a vacuum in the device. The injector dilutes the solution in the bucket at a rate of 16 parts water to 1 part solution. Therefore, the ratio of fertilizer to water that leaves the end of the hose depends on what concentration of solution you put in the bucket. Because the dilution rate is 16:1, put 1 cup of solution per gallon of water in the bucket for every tablespoon of solution per gallon of water that you want to come out of the end of the hose. (There are 16 tablespoons in a cup.)
When you are finished, clean the device by drawing some fresh water in the bucket up and through the injector. Then hang it up so the small brass tube is pointing up. This will drain the water from inside.