Are you longing to enjoy the fragrance and color of roses in your
yard? With thoughtful attention to
planting and care, many types of
roses can be grown successfully in
Central Oregon. The following tips
will help you grow this popular landscape plant.
See "Types of roses" for descriptions of the
general types of roses available. Visit
your local Extension office, nursery,
or garden center for suggestions on
the best types of roses for your area.
Select a rose suited to your area’s
USDA hardiness zone, and look for
disease-resistant varieties.
Location
Choose a spot that will receive at
least 6 to 8 hours of sunlight daily-morning sun is ideal. A site protected
from the wind also is recommended.
Soil
Roses prefer moist, well-drained soil.
In Central Oregon, native soils are
predominantly sandy and can benefit
from additions of organic matter.
These amendments improve water-
holding capacity and aid in initial
plant establishment. Before planting,
you can amend the planting area by
tilling compost 6 to 12 inches deep
into the soil.
Spacing
Space miniature roses about 2 to
2.5 feet apart, depending on variety.
Grandiflora, floribunda, and hybrid
teas should be spaced about 2.5 to
3 feet apart. Check the label for mature height and width before planting.
Digging the hole
Roses are produced using a variety
of methods. Roses usually come in
either a plastic container or bareroot,
and the type determines the size of
the planting hole needed.
For plastic container plants, dig
the planting hole twice as wide as
the container. Then remove the plant
from the container, center it and place
it in the hole.
For barefoot roses, dig the planting hole wide enough so that you can
spread the roots in the hole horizontally. In both cases, dig the hole deep
enough so the graft (thickened bump
on the lower stem) is 2 inches below
soil level (see Figure 1). Planting the
graft below soil level will protect the plant from winter kill. Be sure to
loosen the soil on the sides and bottom of the planting hole, particularly
if compacted.
Most landscaping sites in Central
Oregon have been disturbed by construction activities, greatly reducing
the amount of naturally occurring
beneficial fungi (mycorrhizae) in the
soil. These fungi grow around plant
roots and improve water uptake,
nutrient uptake, and root growth.
They also help to reduce drought
stress (Augé 2004). When you plant
your roses, add mycorrhizae (usually
sold in a dry formulation for home
landscaping use) so that the product
comes into contact with the root system of the plant.
Next, place the rose in the hole (for
bareroot roses, spread the roots), and
refill the hole with soil. You can add
a small amount of organic matter
or compost at a 1:2 ratio (one part
amendment to two parts native soil).
Be careful not to over-amend the
planting hole because the roots of
roses need to adapt to the native soil
for successful, long-term growth.
Finally, water your newly planted
rose deeply. You can add a 2- to
5-inch layer of organic mulch (wood
bark, coarse compost, etc.) to the
soil surface to reduce soil moisture
evaporation.
Watering
Water your rose deeply early in the
day, wetting the entire root ball.
Allow the soil to just barely dry
out between waterings. (A general
guideline is to water approximately
every 5 to 7 days.). If you mulched
the soil surface, the soil will retain
moisture longer.
Be careful not to overwater, and
avoid overhead watering. Water
remaining on the plants can increase
susceptibility to plant disease (e.g.,
black spot or powdery mildew) and
damage flowers and leaves.
Fertilizing
Use a general, well-balanced fertilizer
(e.g., 10-10-10). Make the first
application during bud break in the
spring. You can fertilize every 4 to
6 weeks during the growing season,
but stop fertilization in late summer
(late August or early September) as
the roses begin to go dormant.
Winter care
Unless canes are tall, do not cut roses
back until the spring. Cut tall canes
back to a height of 3 feet in the fall
to avoid winter breakage. After the
ground is frozen, you can add plastic
rose collars and mulch your roses
with wood bark to provide winter
insulation. Wrap the collar around the
base of the plant and fill it with mulch
approximately 6 to 8 inches deep.
Winter watering is very important for rose survival in a high desert environment. Water your roses every
4 to 6 weeks when there is no snow
cover and the ground is not frozen;
two or three times throughout the
entire winter.
Spring care and pruning
Prune your roses in spring as the
weather begins to warm (generally
late April or early May). Pruning
stimulates new growth, so resist the
urge to cut back roses too early in the
spring, or the new growth may get
nipped by frost.
First remove all dead wood and thin
canes to improve ventilation. Cut
back remaining healthy canes to
a height of 12 to 18 inches. When
severe frost danger has passed, cut
canes down to 6 to 8 inches.
During the growing season, roses can
be pruned to encourage more blooms.
When removing spent blooms, cut the
stem back to just above the second
five-leaflet leaf (counting back from
the tip). This will enable new growth
to sprout from that point. Use a slant
cut (Figure 2).
Plant damage
Monitor your roses for signs of environmental, disease, or insect damage
and treat as needed. The most common rose problems include aphids,
black spot, rust, and powdery mildew.
For more information on identifying
rose damage and suggested management, contact your local Extension
office or visit the online Extension
insect and plant disease management
handbooks available online (
see “For
more information,” below.)
Augé, R.M. 2004. Arbuscular mycorrhizae and soil/plant water relations.
Can. J. Soil Science
84:373–381.
Bell, N., D.M. Sullivan, L.J. Brewer,
and J. Hart. 2003.
Improving Garden
Soils with Organic Matter. Oregon
State University Extension Service
publication EC 1561, Corvallis, OR.
https://catalog.extension.oregonstate.
edu/ec1561
Controlling Diseases and Aphids on
Your Roses. Oregon State University Extension Service publication EC
1520, Corvallis, OR.
https://catalog.
extension.oregonstate.edu/ec1520
Pacific Northwest Plant Disease & Insect Management Handbook. Revised
annually by the Extension Services of
Oregon State University, the University of Idaho, and Washington State
University.
https://pnwhandbooks.
org/
Pinior, A., G.S. Grunewaldt, H. Von
Alten, and R. Strasser. 2005. Mycorrhizal impact on drought stress
tolerance of rose plants probed by
chlorophyll a flourescence, proline
content and visual scoring. Mycorrhiza 15:596–605.
There are several kinds of roses, each
with different characteristics and
needs. The general characteristics of
several types are given here.
A climbing rose has stiff stems with
medium to large flowers borne on the
framework of mature wood, which
typically is permanent. Most bloom
throughout the summer, although
a few bloom only in early summer.
Climbers can grow quite tall and
likely will need support. They do not
attach naturally, so they must be tied
to or trained through the support.
Climbers do not need to be cut back
like other roses. After they have
leafed out in the spring, cut off only
the dead portions of the cane. Some
climbers are hybrid teas grafted onto
climbing roots and may have the
same name as a hybrid tea.
Floribundas grow
approximately
3 feet tall and have flowers that
generally are smaller than those on
grandiflora and hybrid tea roses.
Clusters of blooms on short stems
give the effect of mass color. Most
floribundas bloom throughout the
summer, but they may rest during the
hottest weeks.
Grandifloras
have flowers similar
to those on hybrid teas and provide
similar amounts of colorful blooms
for cutting. Flowers are borne on long
stems, often in clusters, and are scented. These roses bloom throughout the
summer. The plants usually are taller
than hybrid teas and generally reach
3 to 6 feet in height. This type of rose
often is sold and used interchangably
with hybrid teas.
Hybrid teas
are long-stemmed, often
fragrant, and excellent for cutting.
This type is what we think of most
often when we hear the word “rose,”
and it is the kind most commonly
used by florists. Hybrid tea roses
bloom throughout the summer and
can reach a height of 3 to 5 feet,
depending on variety.
Miniature roses are smaller versions
of the other types of roses and reach
heights of only 8 inches to 2 feet.
They bloom prolifically all summer,
are fragrant, and generally are more
cold-hardy than floribunda, grandiflora, and hybrid tea roses.
Shrub or rugosa roses often are
referred to as “hardy” shrub roses and
can look like wild roses. Shrub roses
include many plants with roselike
blooms and scents, but they do not
require as much care as other roses.
In fact, these plants require no more
care than a typical shrub (e.g., spirea),
and are a great choice for a high desert area. They bloom throughout the
summer or periodically, depending on
variety.
