Keep an eye on the weather, especially overnight lows. The Denver metro area has experienced a light freeze which may have affected tender annuals, perennials and vegetables. Until the ground is frozen perennials, trees, shrubs and bulbs may be planted.
Don’t forget to water in any new plantings. Make a note on the calendar to provide winter watering to any new plantings monthly through the winter.
Frost may occur anytime now so keep frost blankets or sheets handy to protect tender plants from a light frost so that they can continue to flower or produce fruit. Sometimes we have a frost and then weeks of nice growing weather afterwards.
Keep harvesting now to get the most out of your vegetable plants. Nights are cooling off which is slowing down the ripening process of many vegetables. A little less water will help to stress them into ripening fruit faster as well.
Instead of covering tomatoes to protect from frost, harvest any fruits showing color and they will continue to ripen in your home.
Control broadleaf weeds by pulling or an application of herbicide on a warm day. Take care so as not to injure nearby perennials and shrubs.
Dig up gladiolus, dahlia, begonia and canna bulbs. Store them in a paper bag filled with slightly damp peat moss in a cool dark storage area that will not freeze.
Leave especially ornamental or wildlife-friendly plants standing. Clean up beds for maximum enjoyment by you and the birds.
Gather leaves, and even start a leaves-only compost pile. Run them over with the mower to save space. Once they get crumbly, they make great mulch, or can be turned into beds to add organic matter.
Late-season lawn care: Do your heavy raking now—not in spring. Leave the last mowing 2-3″ long so the lawn does not dry out too much through the dry winter months.
Protect or store weather-vulnerable decorative pots: At a minimum, move pots under cover, where they will at least dry off (to minimize heave/thaw effects of weather). Turn them over on a wooden surface (not concrete) so they will not collect snow and water.