Watering gives life

Create beauty, evolve

Essential for all

Watering is a crucial process in creating and maintaining a garden. When teaching the girls about gardening, we stressed the importance of watering for the overall growth and success of the garden. We also taught them the key concepts involved in watering.

Evapotranspiration refers to the two ways that plants lose water. One way is through evaporation, or the natural loss of water to the air from soil, water, and other surfaces. And the other way is through transpiration, or water lost by the plant itself, primarily from leaves and stems. We kept this in mind as we developed an estimation of how often and how much we needed to water.

It is hard to estimate how often you need to water because it is dependent on numerous factors. Weather conditions are something to take into consideration when trying to find the optimal watering frequency. For example, the amount of rain per season needs to be factored into the equation. One good way to test whether you need to water is to dig up the soil a little and see if it falls apart easily in your hand. If this is the case, it is probably time to water. Your plants will also show signs that they need water. Some signs include wilting, curling leaves, or brown leaves on the lower third of the plant.

Although plants need a lot of water, it is important to keep in mind that too much water creates a lack of oxygen for plants, causing them to show similar symptoms of plants that lack sufficient water.

Another important factor of watering is determining how long you need to water to supply your garden with the adequate amount of water. In order for us to determine the amount of water needed during each watering session, and how long each session should be, we first found the area of the garden in square feet. We found this by splitting the garden into two triangles and finding the area of each, then adding them together to find the total area. We found that the total area is 172.125 square feet.

Area calculations:

Triangle one (small triangle):

A = ½ (l)(h)

Length= 4.5ft

Height= 6.5ft

A = ½ (4.5ft) (6.5ft)

A = 14.625 ft²

Triangle two (large triangle):

A= ½ (l)(h)

16ft + 6.5ft = 22.5ft (length)

14ft = height

A= ½ (22.5ft) (14ft)

A= 157.5ft²

Then, we added them together to find the area of the entire garden.

14.625ft² + 157.5ft² = 172.125ft²

Total area = 172.125ft²

Then, we multiplied the number of inches of water we needed to apply by 0.6 resulting in the number of gallons that you need to apply per square foot. (1x 0.6 = 0.6 gallons per square foot, (172.125ft² x 0.6 = 103.275) or 103.275 gallons for 172.125 square feet.)

Next, we compensated for the inefficiency of our watering technique. We did this by dividing the gallons needed by an “efficiency fraction”: 0.85 for drip irrigation and 0.70 for sprinklers or a hose. (103.275 gallons/ 0.70 = approximately 147.53 gallons.)

To determine how long we needed to run the water to achieve this number of gallons and we placed the hose in an empty 5-gallon bucket and timed how long it took to fill. The 5-gallon bucket filled up in 60 seconds, so we had a flow rate of 5 gallons per minute.

Next, we divided the total number of gallons our garden needs by the gallon-per-minute rate,( 147.53 gallons/ 5 gpm) and came up with 29.5 minutes. This determines how long the hose/sprinkler should be run for.

So, even though it is tricky business finding the optimal watering frequency, it is a good start to perform 2-3 deep waterings per week and see where this takes you. Getting intimate with the garden and observing it daily is a good way to know how often to water.

Here are some important tips to aid in the watering process:

Water when it's needed. Too much water is bad for the garden.

Water slowly. Never water more than about 1/2 inch of water per hour, or too much water will be lost to runoff.

Water deeply. With established vegetables and flowers, 6 inches is a minimum. With established trees and shrubs water 12 to 24 inches or more. As a rule, 1 inch of water will penetrate to a depth of 12 inches in sand and 6 inches in clay. Shallow watering does more harm than good and it discourages plants from developing the deep roots they need to find their own water. Except when you are watering seedlings, soil should always be wet below the top layer.

Water in the morning. Never water during the hottest part of the day because too much water will be lost to evaporation. Watering in the evening sometimes causes problems in humid climates, particularly with overhead watering which wets all the foliage. Foliage that remains wet all night sometimes results in disease and fungal growth.

Don't allow runoff. On heavy clay soil, 1 inch of water will probably cause runoff. At the first sign that the water is not penetrating the soil, turn it off. Irrigate again in an hour or so, after the initial water has penetrated the soil.