SEPTEMBER 2021

    Time is running out for planting hardy perennials.  They should be planted no less than one month before the first fall frost, which usually occurs during the first week of October along the Front Range.
  You may still plant colchicum, a fall-blooming bulb, during this month.  Plant the bulbs two inches deep. Colchicum is a nice companion for other fall-blooming plants such as asters and mums.
  Did you have trouble with geranium (tobacco) budworms eating petunias, nicotianas or geraniums in your containers this summer?  If so, think twice about storing the potting soil for re-use next year.  Budworms over-winter as pupas in the soil.  Temperatures below 20 degrees F. will kill them.  However, if we have a mild winter or if you store the potting soil in a shed or garage that stays warm, the pupas will survive.
  Now is the time to buy spring-flowering bulbs, such as daffodil, tulip, crocus and hyacinth bulbs.  Select bulbs that are large, undamaged and free from mold, soft spots or signs of disease.  Plant bulbs in late September or early October so their roots can become well established before the arrival of cold weather.
  Remove new shoots starting to grow at the base of rose bushes and cut off spent blooms right below the flower rather than at a 5-leaflet leaf.  Taking these steps will reduce production of new growth, thereby helping to prevent freeze injury to the rose bush
   In order to prepare plants for winter dormancy do not fertilize them in the fall and reduce watering.  This will cause plants to slow production of new growth that is easily damaged by autumn frost.
  Be sure to take advantage of sales at garden centers this month.  While spring is the best time to plant trees and shrubs in Colorado, fall is considered the second best time to plant.  However, you should avoid planting evergreens in fall because they tend to dry out during the fall and winter months, and then die.  
  Early September is a good time to seed cool-season lawns such as Kentucky bluegrass and tall fescue.  You may install sod anytime during the growing season, but allow time for roots to become established before the ground freezes.  
  Kentucky bluegrass and tall fescue lawns that weren’t fertilized in August should be fertilized in early September with one pound of nitrogen per 1000 square feet of lawn.  
  Do not fertilize Buffalograss, Blue Grama or Bermuda grass this month.