Operation Kentucky Bluegrass Eradication!

Posted by Nancy Klasky, CSU Extension, City and County of Broomfield

The title refers to what I’ve been calling the efforts my partner, Jim and I have been doing to transform our four-thousand square foot, corner lot, turf yard into something that I’m pretty passionate about, Xeriscaping. Some people think this mean “Zero-scaping” but it is anything but.  The word xeriscaping comes from the Latin xero, meaning dry and scape meaning landscape or view. There was a trend not long ago where people would remove turf and have a rockscape. The problem with rockscapes is that they are heat sinks. They just absorb the suns heat raising temperatures around your home and aren’t very attractive. They also accumulate organic debris and eventually just become a weed breeding ground that is challenging to manage. I experienced much of this during my many years of landscaping work . Xeriscaping, on the other hand is creating a garden that relies on your natural climate. I live in a neighborhood where daily I hear sprinklers going off and lawns being mowed, including our own.  A good portion of Colorado’s population moved here from parts of the country that receive a lot more annual moisture than we do.  What people need to realize is that Kentucky Bluegrass is aptly named, and is not suitable for the Colorado’s semi-arid climate where the average annual precipitation is 17 inches.  Compare this to Kentucky who receives between 42 and 52 inches of annual precipitation.   

Raised bed garden 

We started removing turf by solarization to put a raised-bed garden in the backyard two years ago. We did this by laying down plastic and weighing it down around the edges and in the middle. This process takes about 1 to 2 months depending on how warm the weather is. We had some black plastic which worked well, but since then I’ve learned that clear plastic is actually more effective.  We then built our raised beds and surrounded them with mulch. We live in Longmont where city residents can go get free mulch at the city’s limb diversion center. This works great for this type of area. We add more every year since mulch breaks down and actually will improve the soil composition over time.  The next area we removed the bluegrass from was the other side of our backyard where we are installing a patio. We opted for the plastic solarization method here too.  These two areas eliminated approximately 1/3 of the grass in our backyard. We converted our sprinkler system to drip lines for our vegetable and flower gardens which greatly reduced our water usage. 

This summer we started working on the front yard. This area faces southeast with no shade. The grass has to go! I was a bit daunted just thinking about starting this endeavor because we live on a hill and our front yard has slopes in two directions. There is a 3 foot grade going up to the house, and another slope that is not quite as steep going down the length on the street side. I was worried about drainage and how we would create level gardens.  This hasn’t stopped me however because I’m determined to be an example of a low-water yard in a sea of thirsty Bluegrass! 

Future pea gravel border garden. 

I had drawn up plans based on the square footage and what we want to do. Like many Colorado neighborhoods we do not have any yard between the street and sidewalk, so the heat from the asphalt and cement make this area even hotter. We have finished a 5 foot wide section bordering the sidewalk where we have created a pea gravel garden. This is what we did. After the grass was sufficiently dead we tilled the area and mixed in good garden soil to around a foot deep. Then we added a rock sand mix to add much needed drainage for this area. The top has a 2 inch layer of pea gravel and some bigger rocks for interest. Our plan is to include the most drought tolerant plants in this space such as Ice plant, hens and chicks, yucca, agave and cactus.  I had some hens and chicks that I’d kept in a plastic container for over a year and they are the first addition to our new space.  Hens and Chicks thrive on neglect and do not like a lot of moisture.

Pea Gravel Garden Completion and next levels on the way!

My objective when planting in the front yard is to use all native and water wise plants. Plant Select© is a non-profit initiative that was started by Colorado State University, Denver Botanical Gardens and horticulturists to find the very best plants for our intermountain and high plains regions. I’ve been inspired by the many Plant Select© plants that the Broomfield Master Gardener Demonstration Garden has.  Another important piece to my planning is to benefit the native pollinator populations, and the best way to do this is by using native plants. There are some great books and guides to Colorado and western native plants, and the Plant Select© website also offers many great plant ideas for our climate.

One last area we have started transforming from turf to garden is an area of the side yard. We have removed a lot of soil from the areas already mentioned and this is another very sunny and hot area where the grass was struggling and had to be removed. I wanted a large space to plant gourds and so we

Future Pumpkin Patch 

cut the grass as short as possible and laid down cardboard. Then we just started piling all that soil we’ve been removing from garden and the patio areas. We capped the sprinkler head which will be changed to a drip line and by next spring we should be ready to plant some pumpkins and other fun autumn gourds!   

So far we have removed around 1,000 square feet of our 4,000 square feet turf yard in the two years since we moved in. We are far from done. My hope is to have three quarters or more of that Kentucky bluegrass gone from our lives and to save thousands of gallons of water every year by eventually having established native and drought tolerant plants surrounding our home.  After that is all said and done maybe I’ll look into replacing whatever grass remains with a buffalo grass alternative to save even more of Colorado’s precious commodity that is water!

For information see:

Colorado Water Wise

Water Wise Landscape Design Steps

Xeriscape Turf Alternatives

Xeriscape Soil Amendments

Learning More About Xeriscaping

Guided Tour of a Basic Drip System

Posted by Sarah Schweig, Broomfield County Extension

Drip irrigation is one of the most efficient ways to water the home garden. The slow rates of water application reduce water loss through evaporation and runoff, and the ground-level water application reduces the risks of foliar diseases that can be spread by splashing water.

There are many, many systems and uses for drip irrigation out there.  CSU Fact Sheet 7.402 gives a great overview of the range of options and considerations for each. This flexibility is an advantage of these systems, but the options for equipment and design can be overwhelming if you’re starting from scratch. This post will take you through the basic equipment from water source to garden using an example system based on my own garden. So you can follow along, here are the assumptions I'm working with: This is an add-on system, designed for a home vegetable garden, using municipal water from an outside faucet as a water source. In the garden, I’ll use 1/4 inch drip tape, also called drip tubing, drip line, or emitter tubing.

Drip line is polyethylene tubing with emitters, where water is dispensed, at regular intervals. Typical emitter spacings for 1/4 inch tubing are 6 inches, 12 inches, and 24 inches. Emitters that are spaced up to 12 inches apart can provide consistent moisture along the drip line. 

Photo by Penn State Extension

If you’re using an outside faucet as your water source, you can add a Y-connector and reserve one side for a garden hose. The faucet will serve as the valve and can be opened and closed manually, though automated controllers are also available.

Next, you’ll want a backflow prevention device. These devices allow water to flow in one direction only, which prevents contamination of potable water. This is especially important for drip systems because they lie on the soil surface and can be used for fertigation, both of which are potential sources of contaminants. A good first step in selecting a backflow prevention device is to contact your local water provider, as many municipalities have minimum requirements for backflow prevention devices. The most simple and often cheapest option is an anti-siphon device, also called an external or hose vacuum breaker. As their names indicate, these devices prevent backflow due to siphoning (vs. back pressure). For this minimal backflow prevention approach to be sufficient, make sure you’re using an above-ground connection to the water source located 6-12 inches above the height of your emitters.

Rainbird Faucet Connection Kit

Next in line is the filter. Even if your emitters are clog-resistant, a filter will increase the longevity of your system. If you’re using municipal water sources, 150-200 mesh filters are usually sufficient. The higher the mesh count, the greater filtration provided.

Photo of Y-shaped mesh filter by Berry Hill Drip

The faucet connection kit pictured above has an inline mesh filter pre-installed within the backflow preventer. While these kits are simple to set up, you’ll need to disassemble them to clean the filter. A Y-shaped filter (right) allows the filter alone to be removed for easy cleaning or replacement.

15 psi pressure regulator

Next in the assembly is a pressure reducer, also called a pressure regulator. To select an appropriate pressure regulator, first determine the ideal pressure for the drip line and other components you’ve selected by checking details from the manufacturer. Then, keep in mind any elevation changes from water source to emitters. For every 10 feet in elevation gain in the downstream direction, add 5 psi (pounds per square inch) to your desired pressure.

On the left side of the pressure regulator pictured here, 15 psi indicates the water pressure downstream of the pressure reducer; this number should match the desired pressure for your drip line. On the right side of the pressure reducer, 1/10 - 7 gpm (gallons per minute) indicates the required flow rate for this particular device.

In a home vegetable garden set-up, you’ll likely want multiple drip lines that will correspond to multiple rows of plants. In this case, a header line that feeds multiple drip lines will be connected to the downstream end of your pressure regulator. To connect the header line, you’ll need an adapter, which come in a range of sizes.

Adapter for connecting to 3/4" thread to 1" header.

A typical adapter for this set-up is threaded on one end to fit the pressure regulator; the other end of the adapter is inserted into your header line and secured with a clamp. For a home vegetable garden using 1/4 inch drip line, 1/2 inch polyethylene tubing is usually sufficient for the header, but 3/4 inch and 1 inch tubing is also available.

Header line connected to drip lines with valved couplers.

Finally, you'll need to connect your drip line to the header. You may be able to find 1/2 inch header tubing that has holes at regular intervals that work for your layout; if your tubing is thicker than 1/2 inch, or the available intervals don't work for your design, you can use a hole punch, often called a punch gun, to make holes in the header at your preferred intervals, and use couplers to connect the drip line to the header. One end of the coupler should be fitted to the hole you punched in your header, and the other end should be fitted to your drip tape (1/4 inch in this scenario). Couplers are available with or without valves and can be used as inline connections as well. If you've ever made the mistake of forgetting to install a pressure reducer, you've probably had your drip line burst. When replacing the drip line isn't practical, the damaged section can be snipped out, and a coupler can be used to repair the line. 

These basic components and flow (water source, valve, backflow preventer, filter, pressure reducer, header tubing, and emitter tubing) are the foundation of any drip system, but there is room for great variation. If you're thinking of making the change from hose-dragging, here are some additional resources:

Planttalk Colorado 1621: Watering Colorado Soils

CSU Extension Fact Sheet 7.402: Drip Irrigation for Home Gardens

CMG Garden Notes: Watering Efficiently

Battling Jacques the Rabbit

Posted by: Mary Small and Curtis Utley, CSU/Jefferson County Extension



Rabbit clipped peppers

One of the sure signs that life has returned to our demonstration and research garden here on the Jefferson County fairgrounds is that the resident cottontail rabbit, Jacques, has been busy.

He’s found a good life here with refuge underneath a couple of large shrubs abutting our building and plenty of gourmet food to eat once it gets planted by his humans. No more of that yucky grass and those weird-tasting perennials from the High and Dry garden.  It’s time for the tender lettuce, spinach and other yummy greens.

We thought we foiled Jacques last year by placing the greens in a 3 foot high raised bed, rather than the in-ground bed where they were the previous year.  Voila-it worked! (Against Jack, anyway, not against pests of the human and insect varieties.)

This year Jacques has been getting even by clipping off many residents of our just-planted pepper research bed (at a nice 45 degree angle, as they so artistically do!)  And to add insult to injury, he’s just clipping some of them off and dropping the tops nearby as if to taunt us.  He’s not eating everything, just getting his revenge.



Rabbit proof fence
Two foot wide one-inch poultry netting
stapled to two foot survey stakes



It’s a bit hard to get a harvest and compare performance of pepper varieties when some of them are damaged right at the beginning of their garden life. Thanks a lot, buddy!

So, what to do?  Two foot tall stakes were hammered into each corner of the bed and along the sides. Next, two foot wide chicken wire was tightly wrapped around the stakes. As you see in the photos the fencing is tight to the ground and encloses the perimeter. We hope it will be tough for Jacques to dig under so he will give up and find something else to do.

The fence will make taking data later in the summer a bit more challenging, but at least we should have something to measure!  We’ll see just how clever this guy is as the season progresses and what he decides to do in the meantime.