Landscape Planning Concepts

Kurt M. Jones

Chaffee County Extension Director

When water supplies become stretched, many gardeners look upon their large lawns and wonder about converting it to low moisture plantings.   While lawns have their purpose, making them functional (having only what you need) instead of covering large areas of your lot makes good sense.  So, where do you begin?

Bubble Diagram Example

            First, explore your goals for your landscape.  Do you need an area for your pets or children?  Are there some places in your landscape that are difficult to maintain or keep watered?  Will you need to convert a portion of your existing lawn sprinklers to convert to a perennial bed?

            One trick that landscape designers start with when making a plan is to draw out the existing lot on paper, noting the location of difficult-to-move items like sidewalks, driveways, structures, and established trees.  From there, they draw a “bubble diagram” to note differing effects they wish to make, plant watering requirements, and other desired features such as patios or lawn areas.

            In moving from the bubble diagram to an actual plan, consider other effects that you may wish to accomplish.  If the focal point of your home is the front entrance, then consider plants that enhance that feature instead of blocking the view.  Larger plants like trees can be useful to help “frame” the house features.  When choosing plants for your landscape, be sure to consider not only the size of the juvenile plants, but also mature sizes as well.

One concept that we recommend is the right plant in the right place.  Keep in mind wind exposures, solar heating, and winter conditions when choosing plants.

            In choosing plants, there are several excellent resources available to you.  CSU Extension has many publications available, along with some additional web resources such as http://www.planttalk.org and http://www.answerlink.info which may be helpful.  The SE Colorado Water Conservation District has an extensive demonstration and research garden at their Pueblo location.  Their website, http://www.secwcd.org has many pictures of plants they have on their location, growing characteristics, and other helpful information about maintenance and other items. 

Mid-summer perennial garden

Finally, check with local nurseries to see what they have available and get their advice.  Our local nurseries have plants adapted to our environment and knowledgeable people on staff.  Try to approach them on less-hectic times/days so they have time to assist you!

Getting the right plants is an important step.  Soil preparation, correctly planting transplants, and watering are also very important and often overlooked or not adequately accomplished.  Simply adding 3 cubic yards of compost to every 1000 square feet of bed and incorporating that into the soil to a depth of 6-8 inches will lower your watering requirements, fertilizer requirements, and increase the plant vigor over no soil preparation.  Incorporating organic matter later is much more difficult.

For more information about landscape options, call your Extension office or visit us online at http://extension.colostate.edu/.

Soil Temperature

by Sandy Hollingsworth 

In talking with other Master Gardeners, I’ve found some faithfully rely on soil temperature when planting while others take their chances. I know I’ve been guilty of impatience planting root vegetable seeds, then later tomato and pepper seedlings, too early, then watching them sit doing nothing and never catching up to the ones I waited to plant at a happier, warmer time. The warm sun can make the top of the soil feel warm enough, but down several inches it’s another story. This year I decided to invest in a thermometer to poke into my containers, prepped soil and raised beds to check before planting. I found a 5-inch-long metal stem pocket thermometer, with a probe sheath for storage. It happens to be in centigrade but that is okay as it is easy enough to figure out the conversion to Fahrenheit.

When reading up on recommended planting temperatures I found this summary: “Soil temperature is the best indicator of when to plant each type of vegetable, no matter what climate zone you live in”, said Annie Chozinski, Oregon State University vegetable researcher. “Crops that germinate in the coolest soils (down to 40 degrees F) include arugula, fava beans, kale, lettuce, pak choi, parsnips, peas, radicchio, radishes and spinach seed. When the soil temperature reaches above 50 degrees, Chinese cabbage, leeks, onions, Swiss chard, and turnips can join them in the garden.  At 60 degrees you can sow warm-season vegetables such as beans, beets, broccoli, Brussels sprouts, cabbage, carrots and cauliflower.”

If you are not at higher altitudes with a short growing season like 9300’ at the Gilpin County CSU Extension community gardens, or if you have a warm greenhouse, you’ll want to wait until the soil warms to 70 - 80 degrees to plant warm-season vegetables, or start them inside well in advance. These include tomatoes, eggplants, peppers, melons, tomatillos, cucumbers, corn and squash. Some mountain residents with pockets of warmer micro-climates may be able to grow these warmer season vegetables, but most will be better off sticking to cool season vegetables. Even if you do have a warm micro-climate, do be aware that the harvest will be smaller than lower and warmer elevations.

Our beloved mountain grown potatoes need at least 40 degrees to sprout and be productive. In our shorter, higher altitude growing season cool weather vegetables with shorter growing times tend to be most successful.

Although it is rarely an issue in the mountains except in greenhouses, know that some plants have an upper soil temperature that they will tolerate, such as 80 degrees for lettuce and spinach, and 95 degrees for most anything including cucumbers and tomatoes. Of course, you can plant more vegetables when the soil returns to its preferred temperature if your growing season gives you enough time to harvest it, or you use row covers or other season extension techniques to help regulate the soil temperature.

Here is a sampling of Fahrenheit vs Centigrade conversion if needed:

45 degrees F = 7.2 degrees C

50 degrees F = 10 degrees C

60 degrees F = 15.5 degrees C

70 degrees F = 21 degrees C

80 degrees F = 26.6 degrees C

90 degrees F = 32.2 degrees C

Colorado State University Fact Sheets 7.244 Colorado Mountain Gardening, 7.235 Choosing a Soil Amendment, and 7.214 Mulches for Home Grounds provide more information about controlling soil temperature.  They also explain soil amendments and that reducing surface evaporation and conserving soil moisture factor into soil temperature. Raised beds warm faster plus using south facing areas will usually be beneficial to reduce temperature fluctuations if combined with enough protection from wind. 7.248 Vegetable Gardening in the Mountains includes more scientific explanations about plant base temperature “T-base” and GDU Growing Degree Units, plus tips on seed and site selection.

The thermometer will be a welcome addition to your garden tools and fun to poke around with while you wait patiently for the right time to plant.  Happy planting!

Brunnera

by Sharon Faircloth

Brunnera macrophylla w/ Matteuccia struthiopteris and
 Gallium odoratum and some pushy mint

A lovely little perennial that will brighten up any area with part-sun to shade is Brunnera macrophylla.  It is a member of the Boraginaceae family also known by common names of Siberian Bugloss, Heartleaf Brunnera or False Forget-Me-Not.  My preference is Siberian Forget-Me-Not because its delicate little flowers are such a contrast to the ruggedness of our mountain terrain.  It will easily grow in Zones 3-8. 

Brunnera macrophylla Jack Frost

The leaves are heart-shaped and come in different varieties and shades of green ranging from yellowish to very dark green.  The Jack Frost cultivar has variegated, silvery leaves.  The Diane’s Gold variety is yellow-green.  The heart-shaped leaves range from a petite size to very large elephant ear like size.  The delicate periwinkle flowers shoot up on airy little branches providing visual interest in early summer.  It’s attractive to bees and butterflies and not so much to deer, elk and rabbits! 

Brunnera, Osterich Fern and Astilbe

Brunnera provides an interesting option for ground cover in shadier areas, especially in conjunction with other groundcovers.  It prefers moist, well-drained soil but tolerates dryness once established.  Mulch will help keep the moisture in and protect from winter harshness.  While planting instructions suggest best results come with rich soil (what doesn’t??), I found the plants to be quite hardy once established.  They will grow in small mounds, up to about 12 inches tall and 12-24 inches across.  Plants will self-seed and you can also save seeds to plant in other areas or divide in the spring. 

There are several complementary spreaders (See Fact Sheet 7.413 for mountain specific ground covers at http://extension.colostate.edu/) including Lamium maculatum (Dead Nettle) which has a variegated leaf that has a stand alone interest, even when not in bloom. For people with slightly warmer microclimates,  Galium odoratum (Sweet woodruff) which is also a good spreader with different texture and fragrant little white flowers or Ajuga reptans  (Bugleweed) which has bronze, mat-forming leaves.  This combination provides contrast in color, bloom, height, while sharing the same requirements of soil and light. 

Other ideas for companion plants include Dicentra spectabilus (Bleeding heart) with bright pink or reddish flowers; Astilbe arendsii or A. japonica which also have bright pink, red, white or more subtle colorations with long lasting plume-like flowers; and Matteuccia struthiopteris (Ostrich fern) which is easy to grow and gives, yet another, texture and height that will complement the Brunnera.

Consider incorporating the subtle little Brunnera in your shady landscape and come late spring or early summer, and I think you will be so happy you did!