It is a member of the Rosaceae genus, created in Germany in 1978 primarily as a florist rose.
Osiria rose is a cross between Tea rose and the hybrid ‘Perpetual’ rose.
You will need to search specialty nurseries and plant retailers to find an established Osiria rose.
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Osiria rose is a hybrid which means seeds are not guaranteed to come true to the parent plant.
Soil
Organicallyrich, fertile soilis essential for successfully growing this rose.
Work compost, aged manure, or other amendments in the soil before planting.
The Spruce / Evgeniya Vlasova
A slightly acidic pH level of 6.0 to 6.5 is also important.
If you are unsure about pH, have the soil tested and make necessary adjustments prior to planting.
The soil must also have good drainage.
The Spruce / Evgeniya Vlasova
Water
Water when the top two inches of soil become dry.
Water at the root zone and avoid wetting leaves, flowers and stems.
A layer ofmulchretains soil moisture and keeps the root zone cool.
The Spruce / Evgeniya Vlasova
In colder growing zones with extended freezing temperatures, protect the plant with a thick layer of mulch.
Locating it next to a building or stone structure improves winter survival.
Fertilizers listed for roses are a mix of nitrogen, phosphorous, and potassiumsuch as NPK 18-24-16.
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Types of Osiria Rose
The original Osiria rose was hybridized in 1978.
Since then, other bi-color cultivars hybridized by crossing the tea rose with other rose hybrids, have appeared.
These cultivars produce flowers in a range of colors beyond that of the original Osiria rose flower.
Whether these cultivars are true Osiria roses is a subject of debate.
Here are a few beautiful bi-color rose alternatives to consider.
Weak stems are a drawback gardeners need to improve for this rose to show well.
Using a sharp, sterile pruner, make an angled cut 1/4-inch above an outward-facing leaf.
Pruning above an inward-facing leaf causes branches to cross and increases foliage in the plant’s center.
Take new growth stem cuttings after the plant has bloomed.
Anytime throughout the season is okay but morning will give you cuttings with the best moisture level.
Tip
Rose cuttings have a low success rate for rooting.
Improve your chances by placing several cuttings in a larger pot.
Remove excess soil in spring.
Aphids, caterpillars, sawflies, leafhoppers, and spider mites are all attracted to Osiria rose.
At the first sign of pests, try knocking them off with a strong spray from the garden hose.
It may become necessary to treat your shrub with a high-quality pesticide spray.
Rust, black spot, and powdery mildew are common problems to watch for.
When caught early rust can sometimes be controlled by removing infected leaves.
Treat black spot and powdery mildew with a recommended fungicide.
It is not a heavy bloomer so flowers can be sparse.
How Long Does Osira Rose Bloom?
The shrub grows to maturity in three to five years and should bloom annually provided it receives adequate care.
Even with the best care, disease and pest problems often lead to the early demise of the plant.
What Do Osiria Rose Flowers Look and Smell Like?
Flowers are noted for the distinctly sharp contrast between the insides and outsides of the petals.
The insides feature shades of red to deep, dark hues of burgundy, wine, and magenta.
Outside petals are stark white with some white occasionally appearing at the base of the inside petal.
Flowers have a velvety feel and a deep, musky rose fragrance.
How to Encourage More Blooms
Osiria has a reputation for being a stingy bloomer.
If yellowing is widespread or occurs in young foliage several issues could be the cause.
Overwatering is the first place to investigate.
verify the soil is draining well and the base of the rose does not sit in standing water.
Lack of sufficient light and incorrect soil pH can also cause yellowing foliage.
Curling Leaves
Fungal infections and infestation of sawflies cause leaves to curl.
Treat the rose at the first sign of this problem with a fungicide or appropriate pesticide.
Drooping Flowers
Flowers droop on weak stems.
This may be due to wind or other inclement weather damage.
Osiria rose is a real rose.
Images and photos are often enhanced which can be confusing to the viewer.
The red hue may vary from dark cherry to deep wine.
In 1978 a German rose hybridizer crossed tea rose with the hybrid rose ‘Perpetual.’
The result was a weak plant with an extraordinary bi-colorization.
The rose was primarily used as a cutting rose for florists.
