Monday, August 19, 2019

Sunflower time!

Photo credit: Linda Langelo

Sunflowers are in full bloom from now until October.  They are very drought tolerant.  There are many varieties to choose from to cover your landscape needs.  Among some of the groupings there are tall sunflowers, dwarf sunflowers and colored sunflowers.  

They require 8 hours of sunlight a day.  They are heavy feeders and need fertilization once a week. 

Among the colored sunflowers, here are a couple of examples: 

Photo credit: Dwight Sipler - Strawberry Blonde  
Photo credit: Historymike,  Red Sunflower type

Thursday, July 25, 2019

Phytoplasma in Veronica

Phytoplasma in Veronica, Photo Credit: Linda Langelo

Phytoplasma disease aster yellows which is pre-vectored from leafhoppers.  In the pictures above you are seeing virescent (green flowers) that show phyllody (leafy parts forming within the flower head).

This can occur in alyssum, calceolaria, calendula, china aster, chrysanthemum, cineraria, daisies, delphinium, gladiolus, gloxinia, gypsophila, larkspur, petunia, statice, sweet william, tagestes, veronica, zinnia, and many others including coneflowers

The only thing to do is to remove the afflicted plants.

Thursday, May 23, 2019

Painted Lady Larva

Photo Credit:  Sara Gardner,  Painted Lady Larva
Most people recognize the Painted Lady Butterfly, but not the larva.  If you happen to come across this, do not kill it. 

Photo Credit:  Jean-Pol Grandmont;  Painted Lady
This is the adult butterfly of the Painted Lady.  For 2019 it has already arrived in Colorado.  This season it is expected to be in large numbers.  This seems to cycle through every other year with mass numbers. 

Necrotic Ring Spot

Photo Credit: University of Massachusetts Extension
Necrotic Ring Spot is a fungal disease affecting the root system of the grass especially Kentucky Blue Grass.  The cold and wet springs and early summers are very conducive for this disease.  It can also show up in the fall as well. 

The key cultural things to keep in mind are the following:

  1. Don't over irrigate your lawn in spring.  
  2. Have it aerated to help with soil compaction.
  3. Don't over fertilize.
Here is a good link to learn more:

Red Maple Buds; Photo Credit: Michael Wiedner

With the prolonged cold and wet spring this season, some trees have not started to leaf out.  We might attribute that to the colder temperatures.  The best tip is to see if the branches are still flexible.  Then remove a bud or two and cut it open.  If it is green inside, then sit back and patiently wait.  If the buds are brown inside, then perhaps there was some winter injury or another stress.  In that case, you may have dieback of those limbs.  Wait and see how things progress before making a snap decision on removing parts of the tree or all of the tree.  Call your local Extension Horticulture Agent in June if nothing progresses.

Monday, February 25, 2019

Freezing Temperatures

Photo Credit: Linda Langelo, CSU Horticulture Agent

A fine mist in freezing temperatures covered plants with ice crystals.  The extreme temperature changes throughout the winter can cause freeze damage to our trees.  When the soil temperatures go below 40 degrees Fahrenheit,  the plant's root system is not able to get nutrients or water.  Having plants that are well-hydrated before a freeze mitigates plant damage.

Photo credit: Linda Langelo, CSU Horticulture Agent

Watering each month when there is no snow cover on the ground, helps mitigate plant damage as well. 

Friday, February 8, 2019

A Great Late Winter/Early Spring Flower: Hellebore

Photo Credit: Plant Delights: Helleborus x hybridus 'Cotton Candy' 
This plant stays evergreen in winter.  There are a couple of species that do well in Colorado.  One is Helleborus orientalis and Helleborus x hybridus.  The first is in zone 5 and the second in zone 4a.  They do well in sandy or acidic or loam soil which is well-drained.  The Helleborus orientalis flowers tend to hang down facing the ground.  Other species with newer cultivated varieties have flowers that face upward.  It is really your choice.  However, if you have bees, the down facing blossoms keep the nectar moist.  These are early flowering plants that will help lengthen the time frame for having a food source for bees.   Some varieties start blooming in February while others start in mid-March.  There are varieties that can flower until April or May. 

Hellebores come in a range of colors see the pictures below:

Photo Credit: Plant Delights, Helleborus x hybridus 'Confetti Cake'
Photo Credit: Plant Delights; Helleborus x hybridus 'Golden Lotus'

The Helleborus x orientalis has flower colors of red, pink, white, green and purple.

Photo Credit: Wikipedia; Helleborus x orientalis 'Royal Heritage'

The difference between the flowers of H. x orientalis is they are single flower and H. x hybridus is double flowers.  No the less, a good flower to have as an addition to have after a long winter. 

Thursday, January 31, 2019

Moth Sighting

Photo Credit: Jeff Hooks from North American Butterflies & Moths Website

This moth was spotted in Sterling, Colorado.  The forewing has a pointed tip.  The moth itself is very large, up to 6 inches.  You see pinkish white bands on the forewing and hindwing.  That appears only in females as shown in this picture. 

This is the largest noctuid (nocturnal) moth found in the United States.  It feeds on the leaves of woody legumes at night and hides behind the bark in the day.

Moths do most of the pollinating over butterflies.  Most butterflies feed on nectar, some on sap as in the previous post.


Photo Credit: Carol Dolan 

This butterfly is called a Question Mark.  If you look on the underside, the view facing you in the picture there is a silver marking.  It resembles a question mark.  A silver comma with a dot makes the question mark. 

It is found in open wooded areas and wood edges.  It feeds on sap of elm, hackberry, hops and nettles. It also feeds on carion, dung and fruit. 

This butterfly was spotted in Sterling, Colorado during the summer of 2018.  It is a medium sized butterfly with angled wings.  The forewing has a strongly hooked shape at the tip. 

Winter Watering on Warm Days

Photo Credit: Linda Langelo, Thompson Park, Julesburg, CO

On warmer winter days when there has been no snow cover during the month, it is time to give your trees and shrubs some supplemental water.    On days with temperatures that are in the mid 40's to low 60's, water in the early afternoon.  A little bit of water in the winter goes a long way to keeping the trees and shrubs healthy and out of stress.

Here is a link to a CSU Fact Sheet on Winter Watering:

Watering during the winter when there is no snow cover from month-to-month helps to prevent root damage.  It also helps in areas of your landscape for plants in a south or west exposure.  The soil drys out faster.  Those areas are warmer.  Windy locations in your landscape rob the soil of water.

Any newly planted landscape plants that are not establishment need supplemental water.  With newly planted shrubs it is recommended to add 5 gallons twice a month to the root system when there is no snow cover.