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Beacon Senior News

Garden smarts, September 2016

Sep 12, 2016 11:01AM ● By Kathy Kimbrough

Q. How do I get started incorporating companion planting in my vegetable garden and landscape next year?

Companion planting can mean different things. It can mean combining plants that mutually benefit each other by balancing the pests and predators, visually improving the landscape, or increasing yields in a vegetable garden. For example, marigolds planted in the vegetable garden ward off insect pests. A three sisters garden is where the corn becomes a trellis for beans, the beans provide nitrogen for the corn and the squash’s large leaves are used to shade out weeds. In the landscape, planting a ground cover under trees and shrubs conserves water, restricts weed growth and shades roots. While there is no scientific evidence to support many of the plant associations, there are still many benefits to these combinations. Research different ways to use companion planting to your advantage.

Keep good records and a close eye on what works and what doesn’t.

Q. How late can I apply fertilizer to my lawn, landscape trees and shrubs?

Fertilizing your lawn in the fall is one of the best things you can do for it. In Colorado, timing of fertilization applications is crucial. For deciduous trees and shrubs, apply a complete fertilizer that has the approximate ratio of three parts nitrogen, one part phosphorous and one part potassium after the leaves have dropped off so the plant is able to harden off properly. Evergreens such as pines, spruces and firs could also benefit from fertilization. Late season fertilization should be done when the grass is still green and growing, which is usually until mid-November. To avoid burning the lawn, you must water right after applying the fertilizer. Do not use a slow release fertilizer for the fall application. Cooling soil temperatures slow microbial activity and limit the availability of such fertilizers to the grass. Urea, IBDU, sulfur coated urea and ammonium sulfate are good sourc- es of nitrogen for late-season fertilizer applications.

Q. Is there a local USDA hardiness zone map that can give me some guidance when buying plants for my garden?

I have heard from long-time gardeners that USDA hardiness zones mean very little in Colorado because of our elevation changes and microclimates throughout the state. But for those who need a bit more guidance for planting, Colorado State University Extension has created a local hardiness zone map to show the temperature differences at different altitudes. The Grand Valley is in USDA Zone 7A and the surrounding areas in Mesa County are from 6A to 6B. The higher in elevation, the lower the zone.

Keep in mind these are only guidelines for winter hardiness and temperatures vary from year to year.

I would not count on 7A plants to do well in Grand Junction in the long term. My advice is to use the zone maps for guidance and talk to your local extension office or garden center staff to find out which plants are truly hardy in your area.

Plant of the month: Maximilian Sunflower - Helianthus maximiliani

Fall is my favorite time of year, so I appreciate flowers like the Maximilian sunflower that choose this time of the year to bloom. This towering perennial requires full sun, moderate watering and good drainage, and can reach up to eight feet tall and spread four feet across. Bright yellow blossoms unfurl on the top half and the deep green foliage is attractive all season long. This sunflower puts on a show mid-September through the end of October. It looks great against a fence or wall but it can also be an effective specimen plant in the open landscape. Deer and rabbits don’t bother the sunflower but birds love the seeds, and bees and butterflies love the nectar and pollen. Cut back the stalks after blooming for a tidier appearance through the winter and early spring. Dried flower heads can be left on the ground for the birds.