What do to in your Denver-area garden in October
No need to throw in the trowel for the month of October: There’s plenty to do outside, along with indoor garden projects. Don’t forget to dust off the rake and the snow shovel — both will be getting a workout soon.
COVER CROPS
B Hands-down the best way to improve garden soil fertility, tilth and prevent winter soil erosion is to plant fall cover crops, also known as green manures. Plant in areas where summer vegetables and ornamental annuals grew — anywhere where there’s bare soil. B For fall cover crops, look for winter rye, oats, Austrian winter pea or hairy vetch seeds in garden centers or online. Plant by mid-October, when the ground is still warm, so they sprout, grow and provide coverage all winter. B Follow package instructions for seeding depth and area coverage. They will need water to get established but generally no care after that until
next year. B In late winter, or when the soil isn’t too wet, cut down the growth low to the ground (it may not be very tall), then turn it over, giving it a least two months to break down before planting the first crops of spring.Read more about cover crops: http://www.ext.colostate.edu/ptlk/1616.html
IN THE LANDSCAPE
B Early in the month, there is still time to divide and replant or share overcrowded perennials. The general rule is to divide early spring and summer blooming perennials in the fall, while dividing late summer bloomers in the spring. Cut back top foliage before dividing. B Continue planting spring-blooming bulbs through November as long as the ground is not frozen. Water bulbs during dry fall and winters.Plant violas, mums and pansies, ornamental kales and cabbages for fall color. B Dig up summer bulbs — gladiola, cannas, begonias and dahlia — after frost kills the tops. Dry for a few days and store in sawdust, vermiculite or perlite in a cool, dry place. B Bring herbs such as basil, chives, rosemary and oregano indoors and grow near a sunny window. Carefully dig up a portion of the plant with roots and place in a sterilized container using new potting soil. If gnats or insects have hitchhiked onto the leaves or parts of the soil, treat with insecticidal soap. In some cases, outdoor dug herbs may not produce well from lower winter lighting, so supplement with grow lights as needed. B Harvest pumpkins and winter squash after the vines are frost killed, but before a hard freeze (24 degrees). The skin should be hard so a fingernail cannot puncture. Leave a two-inch piece of stem attached to the fruit. They store for several months in a dry room below 60 degrees. B Parsnips, spinach and carrots can be heavily mulched and harvested throughout the winter and early spring. Collards and kale can be used through frosts or until temperatures kill the leaves. B No needs to toss leaves in the garbage or blow them into the street. Many municipalities have collection or drop off sites through early December. Denver leaf drop and post-Halloween pumpkin compost information at 3-1-1 or https:// www.denvergov.org/content/denvergov/en/ trash-and-recycling/ composting/seasonal-programs.html B Winterize water fountains and
containers this month. Pumps should be lifted, drained, dried and stored.
TREES AND SHRUBS
B We’ve been dry all summer and into fall. How dry are your landscape trees and shrubs? Are they ready for winter? B Plant roots need to be moist going into cold weather prior to the ground freezing. Dry conditions can lead to root and branch death, and less foliage next year, or no foliage. B Trees (both deciduous and evergreen) require moisture to a depth of 12 inches through the growing season. Sprinklers and drip lines may not have provided enough water. It may take time to re-hydrate dry trees and shrubs, so focus on it now while temperatures are mild. Water will soak down much easier now than when soil is cold or frozen. B Check the soil surrounding tree and shrub roots. The easiest way is to poke a long screwdriver into the ground where tree roots are growing (mature tree roots can extend two to four times wider than the height of the tree). If it goes in easily the ground is moist. If you need to push the screwdriver down, the area needs water. B Get the landscape well hydrated before sprinkler turn off or supplement dry areas by using hoses and sprinklers.
FALL LAWN CARE
B Perennial weeds put on deep growth in the fall to get them through the winter, so get a jump on next year’s weeds and remove them now. Hand dig or spot treat. B A fall aeration followed by fertilization is very beneficial to the lawn. The fertilizer moves into the holes left from the plugs and gets right to the root system. Water the lawn a day or two before aerating so deep plugs are pulled. B Areas along the Front Range affected by Japanese beetles can apply products in the fall to kill larvae that live in the soil below turf all winter. Adult beetles emerge next summer, so ridding larvae in the fall may reduce numbers and or turf damage. More information: http://extension.colostate.edu/topic-areas/insects/ japanese-beetle-5-601/ B Schedule the automatic sprinkler shut off for the season, including self-draining systems which may not completely drain (especially on older pipes that have settled). Pipe damage caused by water left in pipes or valves can be costly to repair.
INDOORS
B Take stem cuttings from geraniums for new plants next year. Root 4-6 inch cuttings in fresh potting soil and keep in bright light. Also take cuttings from coleus, fibrous begonias, sweet potato vine and place in water until rooted, then pot up and grow as houseplants near a sunny window. B Plant amaryllis bulbs indoors in
October for December bloom. B It’s time to cue Christmas cactus to bloom from Thanksgiving to Christmas with cooler temperatures (60 degree nights) and nine hours of sunlight daily for approximately six weeks. Reduce watering when the flower buds form, then weekly as the buds swells. Flower color deepens when the plant is allowed to dry out between watering (too dry and the flowers will drop).