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By Betty Cahill, Special to The Denver Post

Anyone who has shopped for clothes knows the expression “one-size-fits-all.” Gardening would be simpler if this applied to plants in all Colorado landscapes and every elevation. Perhaps one-size-fits-most is more realistic when we get right down to it and learn which plants and types can be planted in any given month.

The month-to-month planting chart on Page 8C is a broad-stroke calendar for beginning gardeners along the Front Range. Every garden has the potential to be an outdoor happy place if correct plant choices are made along with understanding your unique growing conditions.

Begin in any month as time and resources allow. Keep these factors in mind for your garden:

  • Gardeners in higher elevations (above 6,500 feet) may need to adjust accordingly by starting later in the spring and ending outdoor planting earlier in the fall.
  • Learning how to garden, and then putting it to practice, is how we begin just about everything in life. View poor performing plants or ones that fail as a learning opportunity.
  • Beginning gardeners can find outstanding garden-instruction classes on plants, planting how-to, design, soil improvement and more by contacting local garden centers, non-profit organizations, botanic gardens, CSU Extension offices and libraries. Many are offered in the fall or after the first of the year and run through the growing season. Quite a few classes and workshops are free or low-cost; some outlets have turned to online instruction. In-person classes may resume down the road.
  • Successful gardening is dependent on each landscape’s growing conditions, cold-hardiness zone and elevation. This includes soil type (clay, sandy, loamy and combinations thereof); location (sun and wind exposure); the watering needs of each plant, which can range from low, to average, to moist conditions. Topography in the landscape matters, too: There may be warmer areas against fences and walls while other spaces might have colder low spots. “Right plant in the right place” should be the guiding force in making planting decisions. Never — let me say it again — never plant or dig in the soil when it is wet. The soil structure will be destroyed and turn to clods.
  • Improving drainage so plant roots have a better opportunity to establish in the soil for healthy growth can require adding soil amendments over time, installing raised beds  or berms, or using containers (which generally are not winter-hardy). Fall is a good time to mail soil samples to labs where it can be tested, providing many fertility measurements that can be helpful to new gardeners. Test results and recommendations for improvement are clearly stated in the report.

Right now across the Front Range, people are planting outdoor trees, shrubs, perennials and turf sod, which generally ends by mid-October. Garlic planting stock and spring-flowering bulbs are often planted until the ground freezes.

After the outdoor growing season, we turn our focus inside to seasonal plants and the wide range of blooming and foliage house plants, dish gardens, cacti, succulents, terrarium plantings, citrus plants, small trees and herbs. (See recent columns on those subjects.)

During and after the December holidays, gardeners who wish to start seeds indoors under lights begin preparing for the new spring and summer outdoor gardening season. Plant lists are made, seeds are ordered, seed trays and equipment are purchased and updated as needed. (A seed-starting and direct-seeding outside calendar for beginners is another column.)

Trees, shrubs, bare-root plants and cool-season grass sod are the earliest group of plants that can go in the ground starting in late winter to early spring if weather conditions permit. Plants showing up in garden centers are good indicators of when plants can go in the ground.

The chart below includes three basic sun locations for placement. It is still a good idea to become familiar with each plant by reading the plant tag, visiting with the garden center experts or reading online about special requirements that the plant or plant group might need. For example, native plants require good drainage and less fertilization than plants like roses, hydrangeas and hostas.

Annual plants are grown for one outdoor season, anytime from early spring to late fall or the first fall frost. Perennial foliage and blooming plants return each year, but many require cutting back the wintered-over dead foliage at the beginning of the new outdoor season in early spring. Spring-blooming bulbs are mostly perennial plants, although some types of tulips naturalize (spread and bloom well each spring) better than others. Summer bulbs like dahlia, canna, gladiolus and others will need to be lifted in the fall and stored inside during the winter or planted new each summer with purchased bulbs.

All newly planted plants regardless of type (tree, shrub, perennial, sod, etc.) require regular watering so the roots establish and grow well. Even if the plant is labeled as needing less water, it will need regular moisture and care for the first couple of growing seasons. Planting during high temperatures in June, July and August requires special attention and care in watering and possibly shading plants a few weeks after planting.

The key to successful gardening in Colorado: Watering in the fall and winter of new plants (and, in many cases, established plants) during dry weeks and months. This means hooking up hoses, watering and draining hoses after each use.

This content was originally published here.