How Much Do I Water In Colorado?
This is definitely the most common question we receive as horticulturists at Nick’s garden center. There is no general answer to this question since it is so complicated with so many variables. There is no ONE right answer. BUT we can simplify the question to help you better understand how much water you may need in your unique landscape.
Lawns: Lawns in Colorado suffer through a constant battle from hot, dry, windy summers to sometimes mild, dry windy winters. What’s the best thing to give a lawn to help keep it green? Water. Unfortunately in Colorado we are constantly under strict water restrictions. There are some soil conditioners to help best utilize your water like Revive or drought resistant grass seed. The BEST thing you can do for your lawn is learn the best maintenance tactics for you.
Below is a quick list of a few tricks and common mistakes that will help maximize your water usage:
- Know your problem areas like, slopes, areas with afternoon sun, areas near sidewalks, and under trees, will need MUCH more water and help than other areas.
- Know the water output of your sprinklers. Pop up rotors and impact rotors will need to run FOUR or FIVE TIMES as long as pop up sprayers.
- Aerating your lawn annually then adding a thin layer of organic material such as compost will help improve soil quality on established/soil compacted lawns.
- Water during the cool times of the day.
- Make sure your sprinklers are covering you lawn adequately in all areas. Most experts will advise that there is at least two sprinklers hitting every area of your lawn.
- Use Revive to help poor Colorado soil absorb and retain water more effectively.
- Use drought tolerant grass varieties such as Blue Carpet grass seed mix.
- Avoid run off due to thick Colorado clay soils or slopes by splitting your watering cycles or having it cycle twice.
- Allow your grass to grow longer and do not cut it as short during the hotter months.
- Take into effect that shady spots, swales, low spots and areas that get run off from your neighbors will not need as much water. Knowing those areas will allow you to adjust your sprinkler’s spray or time to problem areas.
- Recognize stressed grass before it dies. Grass will give tell-tale signs of stress when under watered.
South facing, West facing, sloped, and full sun locations are going to be the toughest spots. If you look at your yard right now, we would be willing to bet the greenest spots are getting a little more shade than the others. The more exposure to sun leads to more stress and evaporation. These problem areas are going to need as much water as your local water restrictions will allow (and then some possibly.) You obviously do not want to break local watering codes, but you can improve the effectiveness of your watering by adjusting watering times, core aerating with adding organic material, and using Revive.
The best time to water is in the early morning when temperatures are the coolest. I will admit that watering in the late evening may increase your odds for pathogens and fungi growth, but I like to split my water cycle in the hottest months to give my grass a little reprieve from the scorching dry day. Splitting your water cycle may also be necessary if you have thick clay soil (which most of us in Colorado do.) Clay soils absorb water very slowly and watering too much at one time will create run off and waste water. Sandy soils aren’t much better since they drain water quickly and will need more frequent watering. Colorado soils are just more difficult to grow a great lawn in. We will go back to advise adding organic material to improve you soils. If you think of the rich dark soils back East that will grow anything that falls into it, those are MOSTLY organic material.
Knowing the output of your sprinklers and getting adequate coverage is one of THE most important steps to having a healthy lawn. Impact and pop up rotors put out ¼ or less water per minute than pop up spray heads. To give you an idea Aurora Water recommends you water your lawn 7-9 minutes with pop ups versus 40+ minutes with rotors. A “rotor” is any kind of sprinkler that moves back and forth, be it a constant spray or the older “chink, chink, chink” kind (impact rotor.) Most sprinkler systems are designed to have lots of overlap on a lawn. Do not misconstrue this as wasted water. It is there to ensure even and adequate coverage. Watering the sidewalk or your driveway is wasted water.
When stressed by drought grass will let you know in a couple of ways. It becomes a dull grey-green and when walked on will show visible footprints for a length of time. Keep in mind that it is unlikely this will happen evenly across your yard since some areas are likely to get more sun than others.
New Plants, Trees and Shrubs
Again because everybody has different situations in Colorado and conditions may vary even from one plant to the next there is no “magic bullet” for this answer. There are few general rules to follow and some common sense approaches to be able to figure out your right answer. I have created a quick list of common tricks misconceptions and problems we face in Colorado. Below the list I explain the ideas in more detail.
- Do not guess if a new plant needs water. Checking for yourself will overrule any guide you read on how often to water. Investigate 2 inches down to see if there is moisture in the soil or use a moisture meter. You won’t have to do this many times before you learn how often your new plant needs to water.
- Deep and infrequent and ‘moist but not wet” are the key phrases to describe the best watering practices.
- Smaller plants will need water much more frequently than larger ones if you do a proper soaking.
- Cooler weather or rain means much less frequent watering 1-2 times a week versus 3-4 times. Extreme heat will add even more water needs. Sometimes every day for bedding plants.
- Colorado clay does NOT drain water quickly. Too much wet soil for too long WILL kill your plant and you won’t know it’s dead until it’s too late.
- Sand does drain water fast and will need more frequent attention.
- Be sure to mix in about 30% compost when planting. This will help both clay and sandy soils.
- Make sure water is getting directly to the roots and not just soaking the soil around it. New plants can sometimes die from lack of water when the surrounding soil is wet. Dribble water from a hose into the center of your new plant.
- Don’t just water the surface of the plant. Roots go deep. It may take a few minutes to get the water to the bottom of the root system.
- I see most dead plant due to over watering than under watering.
- Under watered plants can sometimes be brought back from the dead (if you catch it.) Over watered plants are usually too severely damaged to be revived.
- Rain CAN add moisture to the system but it’s usually insignificant to help much. You should always check after a rain to see if your plant needs water or not.
Now that you have (hopefully) read the tips, we will offer a few GENERALIZATIONS for watering frequencies for new plants during a regular warm season. The water needs could easily double or more when hotter. Cooler and wetter seasons will also reduce the new plants needs for water. Established plants will more than likely need to be watered much less as well.
Six packs, 4½” pots, and some gallon sizes, water 5-7 times a week:
- 1-2 gallon sizes, water 3-4 times a week
- 3-5 gallon sizes, water 2-3 times a week
- 5-10 gallon sizes, water 1-2 times a week
- 15+ gallon, water 1-4 times every two weeks
Again, these are general guidelines and if you are ever in doubt if a plant need water check the soil for moisture. If the surface is dry poke your finger at least ½” deep, if the soil is still moist do not water, if dry, give water. Remember smaller pots have less soil and dry out quicker.