CSU Extension Pueblo County Horticulture Program

Report: Pine beetle destruction expands dramatically on Front Range
Things are looking rough for our trees here in Colorado. To get the latest numbers and outlook you can read the article linked below or follow its links to the original report for an even more in-depth take.

Read the article here: https://warnercnr.source.colostate.edu/report-bark-beetle-outbreaks-expand/

Report: Pine beetle destruction expands dramatically on Front Range - Warner College of Natural Resources Colorado’s top forest health concern is a mountain pine beetle outbreak on the Front Range that has expanded by nearly 150% from 2024 to 2025, according to a Colorado State Forest Service report.

Thin That Fruit

Although ideally you should be removing extra fruit i.e. thinning your fruit trees from April through mid-May, I would say you’re not too late if you get out there this weekend and take care of it. Thinning allows the trees to direct their resources to fewer fruit, meaning those fruits will be able to reach larger sizes with likely better flavor. It also helps with trees who have to deal with a lot of extra weight as fruit ripens such as peaches, reducing the chances of branch breakage.

If you’ve noticed that your fruit trees have lost some fruit already, you’re likely seeing a ‘natural thinning’ whereby the tree decides there’s too much fruit and will lighten its own load. You can be more strategic than the tree though and make sure that the load you leave on is well-spaced and looks to be manageable by the strength of the branches present.

To remove the fruit: Rather than pulling it from the branch, fruit should be hand thinned either by 1) twisting it off the stem, 2) pinching off the stem between the fingernails of the thumb and index finger, or 3) using clippers.

Apples: thin apples to six to eight inches between fruit, and to one per cluster by mid-June or when fruit is nickel to quarter sized.

Plums and Pluots: Thin to four to six inches apart.

Peaches: For quality fruit, thin peaches to six to ten inches between fruit prior to the fruit reaching one inch in diameter. If you wait too long to thin, the fruit will be small and not juicy. Thinning also helps control codling moth in apples, as the female moth likes to lay eggs between touching apples.

Cherries: Cherry fruit is not generally thinned since the fruit is small and thinning would not improve quality.

Growing Tree Fruit in Colorado Gardens:https://cmg.extension.colostate.edu/Gardennotes/771.pdf

Keep An Eye Out for Pinon Needle Scale

Unfortunately, I’ve seen a lot of this pest around Pueblo this year. If you have pinons on your property, I encourage you to go take a look and see if your tree is suffering under their pressure as well. I’m including resources below that can help you confirm if what you’re seeing is the scale and your options on what to do about it. At minimum, it’s good to know what your trees are dealing with so that you don’t add additional stress and can take measures at the appropriate times to help them fight off the infestation. Please remember that in the case of Pinon Pines, increasing your irrigation amount may do more harm than good as they particularly hate having ‘wet feet’ or getting too much water and can quickly go downhill when this happens.

Pinyon Pine Diseases and Insects: https://extension.colostate.edu/resource/pinyon-pine-diseases-and-insects/

Pinyon Needle Scale, Insect of Interest:https://wci.extension.colostate.edu/wp-content/uploads/sites/14/2017/04/PinyonNeedleScale.pdf

Scale Insects Affecting Conifers: https://extension.colostate.edu/resource/scale-insects-affecting-conifers/

Don’t Forget the Night Bloomers

It can be easy to overlook the needs of those we rarely if ever see but our native moth species would certainly appreciate it if more of us made a point to plant flowers that are meant for night pollinators. Here’s some ideas for our area:

Colorado Four O'Clock (Mirabilis multiflora)
Tufted Evening Primrose (Oenothera caespitosa)
Pale Evening Primrose (Oenothera pallida)
Common Evening Primrose (Oenothera villosa)
Yucca (Yucca glauca)
Datura / Jimsonweed (Datura wrightii)
Moonflower (Ipomoea alba)
Flowering To***co (Nicotiana alata)

(Photo: Sacred Datura, Colorado Springs Utilities)

Native Plant Profile: Prince’s Plume

(Photo: https://earth.callutheran.edu/)

Scientific Name: Stanleya pinnata

Zones: 4-8

Size: 3-6 ft. x 2-3 ft.

Preferences: Dry hillsides, mesas, rocky places; plains, foothills, shrub steppe, pinon-juniper, montane, sandy or gritty soils. Low to very low water needs. Once established likely won’t need irrigation.

Tips: Dislikes competition. Give it space and place it like you would a shrub.

Where to see in Pueblo: There’s a good amount down at the Nature and Wildlife Discovery Center around this time of year, but they’ll grow anywhere the conditions are what they like. I have one in my native plant garden and it attracts a large variety of pollinators and is certainly a fabulous eyecatcher as well!



-Information sourced from The Rocky Mountain Plant Primer, Lauren Springer and Bryan Fischer

The Pueblo County CSU Extension office will be closed Wednesday, June 3, for Pueblo County Employee Appreciation Day. State employees will be working remotely.

A Bit of Tang?
Maybe you like it in pie form, as a crisp, or as a jam. Whatever form rhubarb takes in your kitchen, it’s happily that time again to harvest, cook, and store it away for future rainy days when you’ll be longing for its delightful tangy zing. Below is CSU’s full profile on Rhubarb in Colorado that explores its uses, nutrition, etc. and another article by Ohio State that goes further into the growing of it. Additionally, I couldn’t help but include a fun recipe for a mocktail that some of you daring foodies may want to try out 😊.

Colorado Rhubarb:https://foodsmartcolorado.colostate.edu/wp-content/uploads/2021/04/Colorado-Rhubarb.pdf

Ohio State, Growing Rhubarb: https://ohioline.osu.edu/factsheet/hyg-1631

Rhubarb Mocktail, Throughthefibrofog.com: https://www.throughthefibrofog.com/rhubarb-mocktail/

The Pueblo County CSU Extension office will be open at 9:30 AM with limited staff on Monday, June 1. Other staff will be available remotely.

“I loved rhubarb, that hardy, underappreciated garden survivor that leafed out just as the worst of winter melted away.”
-Judith Fertig, The Memory of Lemon

Roses!

None of us gardeners can be good at growing everything. Admittedly, as much as I love roses, I’m a complete novice when it comes to giving them the best care on the best timeline. Whether you’re trying to do better by your roses too or are just starting to really get interested in these lovely garden standbys, take a break from outside, grab a cold drink, and relax while watching this ‘Roses for Beginners’ video shared by the American Rose Society, https://www.youtube.com/watch?v=C-ZKw71RxOA&t=1s