CO-Horts Blog

Tuesday, April 30, 2019

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

Thursday, April 18, 2019

When a Houseplant Outgrows its Home...

By: Sherie Caffey, Horticulture Agent, CSU Extension-Pueblo County

    It’s spring time and everything outside is starting to green up and get growing! The outdoor plants aren’t the only ones gearing up for a growth spurt, your houseplants are waking up from their winter snooze and starting to grow more as well.

    Give your houseplants a little spring cleaning, as dust tends to settle on the leaves. With more active growth, also comes a greater need for water and fertilizer. Your plants will also benefit from a breath of fresh air on warm days, but don’t forget to bring them in during our still chilly nights.

Some supplies you will need
    One spring time houseplant chore I needed to get done was dividing my peace lily (Spathiphyllum sp.). This is one of my favorite houseplants, because it’s very resilient and can handle the extreme neglect it receives from me. Dividing is done when the plant has become too overgrown for its container. One sign that a plant has outgrown its home is that it is difficult to keep it watered, and the plant wilts often between waterings. When you pull the plant out of its pot, you will likely see many crowded roots. Dividing is best done in spring, since the plant is actively growing.

The split plant with cleaned and teased roots
    To divide a houseplant, first, place your hand over the top of the pot and invert it. Give the pot some gentle squeezes or taps to dislodge the plant. Gently lay the plant down on its side on your work surface. Tease and loosen the roots, removing the soil from them. If the roots are very thick and overgrown, you may have to use scissors or a knife (sterilized) to help you separate the plant, otherwise just gently pull it apart, and split it into two or three smaller plants. Cut out any roots that have died. Each new plant should have a good amount of roots and at least a few leaves.

Two plants!
Crown placement

    Fill your new pots up about a third of the way with soil. You want the new plant to be positioned so that the crown is a couple inches from the top of the pot. Spread the roots out and set the plant in place. Fill soil in around the plant. The crown should be at or just above soil level. Water the plant until water runs out of the bottom of the pot. Now you have two plants that will be much happier in their new digs!

Wednesday, April 17, 2019

Battling Japanese Beetles

Posted by Lisa Mason, Arapahoe County Extension

If you live in certain parts of the Denver Metro area, you are probably very familiar with this pest. Littleton and other parts of Denver are inundated with this insect starting around mid-June.

Japanese beetle population levels in Colorado. Source: Colorado Department of Agriculture

This invasive beetle has two unique challenges: 1.) Japanese beetles cause damage during the larval/grub stage in turf grass, and adults cause damage by feeding on a variety of landscape plants and trees, and 2.) adult beetles feed on blooming flowers at the same time pollinators and beneficial insects are pollinating those flowers, which limits control options.

Japanese beetles were first introduced in the United States in 1916 and has spread throughout the US via nursery stock. The beetle was brought to Colorado in the 1990s but only recently have populations grown considerably. The larval stage feeds on the roots of turf grass, and the adult beetles feed on vegetation, including popular plants such as roses, crabapples, Virginia creepers, and linden trees. They can feed on over 300 plant types.

Japanese beetle life cycle. Source: University of Minnesota
A Japanese beetle larva. Source: David Cappaert,
An adult Japanese beetle. Source: David Cappaert,

You won’t see adult Japanese beetles appear until around mid-June, but now is the time to start planning for their return. Here are some things you can do:

For now and longer-term:
  • Keep your plants as healthy as possible. A healthy plant will be able to sustain more damage. Practicing good cultural care will help reduce the stress on your plants.
  • Keep turf as healthy as possible, too. A strong root system will be able to tolerate more feeding from grub.
  • We are providing a perfect environment for Japanese beetles: well-irrigated turf provides their habitat and a wide variety of plants provides their diet.
    • Consider planting other cultivars or plant varieties in the landscape. Research which cultivars are not susceptible to Japanese beetles.
    • Be creative with plant selection! Evergreens, annuals, perennials, some vegetables, and many tree varieties are not susceptible to the beetle.
  • Research your options for biocontrols and pesticides.
    • Choices can be limiting depending on if pollinators are foraging on the same flowers that the Japanese beetles are feeding on. Pollinator-safe options include Bacillus thuringiensis var. galleriae (marketed as beetleGONE!, beetleJUS!) and chlorantraniliprole (marketed as Acelepryn SC).
    • Look for plants that do not produce flowers or their flowers bloom at a different time than when the adult beetles are active. For example: crabapple trees bloom in the early spring when adult beetles are not active and other treatments may be an option.
    • Remember the label is the law! If you chose to apply pesticides, the directions must be followed exactly.
    • For a complete list of control options on foliage and turf and how they affect pollinators, see the Japanese Beetle factsheet.

When the beetles arrive:
Hand picking Japanese beetles off roses. Source: Lisa Mason
  • Hand-pick Japanese beetles to your hearts content! You can squish them or dump them in a bowl of soapy water. This effort may seem tedious, but keep in mind each female beetle can lay 40-60 eggs. Hand-picking will also reduce the volatile attractants produced by plant wounding.
  • Think twice before using Japanese beetle traps. Research shows that traps can attract more beetles to the area. As they fly towards the trap, they may find new food sources along the way. If you choose to use traps, place them at least 30 feet from any vegetation that the beetles will eat.
  • Make sure you have grubs in your turf before treating the turf with products. Checking can save you time and money. Grub damage looks very similar to other turf issues. Try doing a “tug test”. If you tug on your turf and the grass pulls out of the ground immediately, then you have may have grubs that have been feeding on the roots. If the grass is rooted into the ground, you may have another issue.
  • If you do have grubs, consider drying out the lawn when the grubs are active. They need well-irrigated soil to survive.

A native bee and Japanese beetles on a rose. Source: Lisa Mason
Are geraniums a plausible solution? Not likely. Research indicates that if Japanese beetles feed on geranium flowers (not leaves), they become paralyzed and rarely recover. However, geraniums are not a very favored host plant and if more attractive plants are nearby, such as roses, Virginia creeper, or lindens, then they would not visit the geraniums.  Also, if they do feed on geraniums, they mostly feed on the leaves, which are not toxic.

Japanese beetles are here to stay, unfortunately. With some longer-term landscape planning and persistent treatment efforts, we can try to disrupt the perfect environment we have created for them. 

More questions on Japanese beetle? The Japanese beetle factsheet is a great resource! You can also call your local county extension office.

Best of luck battling the beetles this summer! 

Friday, April 12, 2019

Cassey Anderson- CSU Extension Adams County

Are you looking for something to do this weekend? The Front Range Extension offices have joined forces to put together an amazing day of classes and vendors at the 1st Bank Center in Broomfield. Registration is only $10 and you can participate (kids and your adults 17 and under get in free!)  in a variety of classes and demonstrations. Come meet your local extension agents, coordinators, local experts and specialists, and Master Gardeners and have a chance to learn about all that Extension has to offer!

There will be an entire classroom devoted to learning about making beer and cheese! There will also be numerous speakers on topics including water-wise gardening, landscape weeds, rain barrel use, rainwater harvesting, edible landscaping, backyard greenhouses, backyard fruit trees and small fruits, native plants and more. If concerns about insects are more your speed you can learn about pests in our area such as Japanese Beetle or Emerald Ash Borer. 

There will be a variety of hands-on demonstrations and activities: 4-H will feature STEM rocketry and robotics, helmet safety, and if the weather permits 4-H will have animals on show. Horticulture experts will demonstrate tree planting, and Master Gardeners will be showcasing vermicomposting.
If that isn’t enough there will also be food trucks on site so you don’t have to go far afield to get some food in between all of the incredible classes and programs you can choose from! Registration day-of is only $10 payable at the door. For more details on classes and events please go to:

Wednesday, April 10, 2019

Loving my spring-blooming bulbs!

Posted by: Alison O'Connor, Larimer County Extension

Last fall I blogged about planting the bulbs that I bought a little haphazardly and in great quantities. But all the hard work paid off, because they are (were?) blooming beautifully. [We're currently in the middle of a spring blizzard, so the blooms might be impacted by the wind and snow.] Last weekend the bulbs were beautiful--not quite the swaths of daffodils they have in England, but not bad for Windsor, Colo. Even a little color after a long winter is welcome.

I have to admit that the hyacinths are my current favorite, just because they smell so wonderful. With the windows open, you can even smell them indoors--a gentle, sweet odor.
Daffodils and hyacinth
Right after this photo, like the very next day, the pink hyacinth opened and they are a beautiful magenta pink! Almost like raspberry sorbet. Yum.

I still love the "minor" bulbs--the little guys that you need to stoop down to appreciate. One is the reticulated iris. The patterns in the flower are spectacular.
Reticulated iris. It had just sprinkled, so I caught the droplets on the flower.
I have crocus in yellow, white, and purple. The yellow ones were especially cute this spring. Is it just me, or if spring was a color, it would be yellow?
Yellow crocus...on their way out.
The tulips have yet to open (or they were eaten by rabbits). And there are more daffodils waiting for their moment. I'm excited to see these bulbs multiply and increase their impact and curb appeal over the next few years. Happy spring!
Cheerful yellow daffodils.

Monday, April 8, 2019

Spring Has (Not Quite) Sprung

Andie Wommack, Douglas County Extension Agent

A couple weeks ago, we saw temperatures above 70 for the first time this year in Castle Rock. I was so excited and spent as much time outside in the sun that I could. That Friday, it snowed. There was much wailing and gnashing of teeth (at least at my house). This is the time of year when many of us start itching to get outside and work in our yards. This year has seemed much more wintery than ones in the recent past, which is contributing to the itch of needing to be outside.

While it’s not quite time to be planting your garden outside, there are several things you can
do to prepare your yard and garden for the coming gardening season. One main gardening task that most people like to do in the spring is fertilize or add organic material or compost. This may be unnecessary. Soil tests are an important tool when planning what amendments to add to your garden or landscape beds. Excess nutrients from home landscapes can be a major detriment to the local water systems. Landscapes can have a positive effect on water quality because they slow rain water down and help filter out impurities, but if you are fertilizing unnecessarily and/or watering too much, it contributes to pollution problems. The three main nutrients in any fertilizer are nitrogen (N), phosphorus (P), and potassium (K). There will be a series of three numbers on any fertilizer that tells you the NPK content percentages. For example, if a 12lb bag of fertilizer says 34-0-4, it contains 34% (4lb) nitrogen, no phosphorus, and 4% (0.5lb) potassium. Fertilizers will often contain other nutrients like sulfur or iron, but you have to read the label to find out how much the bag contains. If you get your soil tested, it will give you recommendations for amendments based on any nutrient deficiencies that exist. If the soil test indicates a need for one pound of nitrogen per 1,000 square feet, you would use that recommendation to determine how much of the 34-0-4 fertilizer you would need to apply (three pounds for 1,000 square feet). However, if no phosphorus or potassium is recommended, you would not want to use that particular product. Look for something with zero percent phosphorus and potassium so you aren’t applying unnecessary nutrients to the ecosystem.

Now is a great time to start cleaning up your landscape. Check your area for any damage that may have occurred over winter. Make sure any trellises, raised beds, or other garden structures don’t need any repairs, and check trees and shrubs for any broken branches.
Also check trees for any branches that are crossing each other as those may become damaged when rubbing against each other. Do you best to remove snow during heavy snowstorms to prevent branches from breaking under the excess weight. Cut back your perennials and grasses that were not trimmed back in the fall if the weather is nice. It is important to leave these plants over the winter for food and habitat.

Clean up your lawn by removing any stray leaves, twigs, or other winter debris once it is clear of snow. If you have areas that need to be reseeded, make sure you do not apply any crabgrass preventer (pre-emergent) as this will also prevent your grass seed from growing. Delay turning on your irrigation system as long as possible to help conserve water and money. Generally, precipitation is most bountiful in the spring which will provide the necessary moisture for your turf. Daily irrigation is only necessary for germinating new seed or establishing the young roots of new sod. Daily watering a mature lawn encourages shallow root systems which will greatly reduce the turf’s drought tolerance. Bluegrass is relatively drought tolerant if managed correctly. Spring is also an excellent time to aerate your lawn. Aeration works best when plugs, or cores, are pulled from the soil. These should be two to three inches deep and no more than two to four inches apart. This will require several passes across your lawn. This helps reduce compaction which allows roots to grow easier through the soil.

So, while it may not be quite time to start planting your veggie garden with the potential for snow on the horizon, there are plenty of things you can do to be active outside!

Thursday, April 4, 2019

Spring's not so nice things

By Carol O’Meara, Boulder County Extension 

In an annual emergence in spring, the queens are awakening, shrugging off a winter’s sleep with conquest on their minds.  They’re strong, hungry, and looking for real estate in which to build a nest – probably under your porch, your patio, or in the rock walls of the raised garden.

Western Yellowjacket
  Yellow jackets are beginning their year, and to keep your yard from the black and yellow bullies, these queens must die.  In winter, yellow jacket colonies die, leaving only queens survive.  They emerge when the weather warms in spring to begin colonization of our landscapes. Waking up eager to feed and alone, they’re the ones out foraging for food; by trapping her, you will prevent hundreds of her offspring from harassing your family in fall.

Put out your wasp traps now, filled with heptyl butyrate, or design your own with chunks of cantaloupe – all it takes is a 2-liter sized pop bottle.  Cut the top off the bottle at the shoulders, turn it around and slide it into to the lower part of the bottle so the neck points inwards, and staple this together.  Before you fit the top on, fill the bottle with a small amount of cantaloupe.  Some wasps prefer protein, so make another trap and put a bit of lunch meat in it.  Hang these away from your house. 

European Paper Wasp
 Another wasp that’s becoming active is the European Paper Wasp, Polistes dominulus.  This builds open-faced nests up in the eaves, inside sheds, and in other spots located above ground.  They aren’t aggressive unless you get too close to the nest; if you do,  then they may sting.

 Paper wasps look a lot like yellow jackets but aren’t attracted to traps at all.  They’re predators, hunting the yard for soft-bodied insects.  They, too, start the spring with a single queen per colony, so if they bother you, wallop them with a flyswatter.

 As long as we’re on a painful topic in gardening, it’s time to talk ticks.  Good health in gardening involves understanding potential risks and avoiding them where possible.  Gardeners are familiar with mosquito avoidance, but ticks remain a bit less publicized, and perhaps less understood.  Of the 30 species we have in Colorado, none are those known to carry Lyme disease, which is fairly serious in the eastern U.S..  However, ticks can carry other problems and gardeners should take steps to keep themselves free of them.

 Ticks begin activity in early April when the young hatch from eggs and crawl to the top of tall objects to wait for an unsuspecting animal to walk by.  Size is relative when you’re a newly hatched tick nymph, and a tall object to a tick is a grass stalk.  There, at the top of the stalk, many ‘ticklets’ bivouac – a cheery term for describing a mass of the tiny creatures hoping for dinner to come to them.

 Keeping ticks at bay involves simple precautions.  If possible, stay away from areas that ticks like, such as animal trails through brushy areas, at the edges of fields, wooded or shrubby areas and grasslands.  But if you want to enjoy the outdoors, a better approach would be to wear protective clothing that includes long pants with socks pulled up over the lower cuffs.  Repellents may also be applied to clothing to help ward off ticks.

If you find yourself in tick country, don’t panic.  Ticks take time to attach, usually several hours, so there is time to check yourself and remove them.  If possible, have another person help you check – nothing quite says “I love you” like checking one another for parasites.