Usually made from old tires or recycled plastic, soaker hoses are ecologically correct as well as functional. They look like a rough black garden hose, with a female hose fitting on the faucet end and a male fitting with a removable cap on the other end. In use, soaker hoses leak water through millions of tiny pores. They are used with low-pressure systems, so can be classified as drip irrigation emitters.
Pressure
Soaker hoses must be used with low pressure. If used at normal household pressure (about 60 psi), water will force many of the micro-pores larger and squirt out in streams that destroy its effectiveness as a soaker. If you wish to use a soaker hose as part of a hose-end system, use it with one of the small pressure-reducers that fit inside the female connection.
Soaker hoses are not pressure-compensated; they are quite sensitive to pressure, and lose pressure all along their length. For this reason, try to lay out each hose so it is level.
To see how evenly your hoses are watering, place pans of the same size under each end of a hose in use, and measure the amount of water emitted in a given period, such as 15 minutes. If the plants at the end of the hose aren’t getting enough water, break the hose into shorter lengths. It is also helpful to make loops of soaker hose, with both ends going into a T connection attached to the header line.
This pressure loss is less of a problem with a hose-end system because you can lay the hose out in different directions each watering. The end that got less water this irrigation will get more water next irrigation.
Using Soaker Hose
As a temporary hose-end watering device, soaker hoses are simple to use, especially for plants in rows, such as a vegetable garden. Lay out the soaker hose where you want it, attach a garden hose to it, and let it run for a couple of hours. Water will seep into the soil as it does from drip emitters, watering the plant roots without wetting much of the surface soil.
Soaker hoses are especially useful on hose-end systems in mulched beds. Sprinklers in mulched beds must wet the mulch all the way through before any water reaches the soil. Since plant roots don’t grow into the mulch, this water isn’t available to plants and evaporates away without benefiting the garden. Some mulches will absorb considerable quantities of water before becoming saturated and passing water through to the soil. Soaker hoses, by concentrating all their water in the area under the hose, wet little mulch and pass water through much more quickly.
As part of a drip system, soaker hoses are emitters, releasing about 1/2 gph of water per foot of hose (depending on pressure). Unlike other emitters, they don’t plug up easily. However, they are not plug-proof. They can become plugged after long use or if the water is dirty with silt or algae.
Soaker hoses can be laid out in parallel rows to evenly water an area. In this case, use the same criteria for spacing as you would for drip emitters: from 1 foot apart in sandy soil to 2 feet apart in clay soil. They can also be snaked between plants in irregular groups. Water trees and shrubs by circling the plant with a soaker hose, about 2/3 of the way from the trunk to the drip line. Attach both ends to a T connection that is attached to the supply line.
Use this same method of making a circle with a T connection to water larger planters. Use 1/4-inch soaker hose for planters.
Other Types of Soaker Hose
The first soaker hoses were made of canvas sewn into a hose. They worked well, but the cotton fabric rotted quickly under garden conditions. This type is probably no longer available.
Another older type that is still available is a flat plastic hose with tiny holes pricked along one side. When used with the holes up, it became a sprinkler. With the holes down, it is a soaker hose.