How To Grow And Care For Osiria Rose

You may have seen images of the two-toned hybrid tea Osiria rose (oh-SEER-ee-uh) online and thought that they were too good to be true. In many cases, you would be correct. 

Blooms of The Osiria Rose
Osiria hybrid Tea Rose

Recently quite a few Photoshopped images of this pretty rose have been posted, and this has led to disappointment when gardeners have ordered the rose and found the results to be impressive, but not quite as stunning as the images they have seen.

Even so, Osiria rose is a very lovely hybrid tea that does produce two-toned petals and has a very sweet, strong fragrance. Petals are typically bright red on the topside and white or silvery on the reverse.

Want Brighter Roses?  – Try Epsom Salts for Roses 

While the blooms are quite stunning to look at, this delicate hybrid perennial rose can be very challenging to grow.

Like all roses, osiria is a member of the genus, Rosa (RO-zuh) and the Rosaceae (ro-ZAY-see-ee) family of plants.

The plants’ botanical name, Osiria, is a reference to the lost Athenian city, Osiria (land of Osiris). Like Atlantis, this ancient city is now hidden beneath the sea.

You may also hear this rose Osiria referred to as the Korsir (KORsir) rose in honor of Reimer Kordes , who originally developed the rose years ago in Germany in 1978. The name, Osiria was given to this red blend hybrid by Willemse France, who introduced the rose in Paris.

Osiria Rose Care

Size & Growth

Rose Osiria is an upright shrub that grows to a maximum height and width of 3’ to 4’ feet. These rose bushes can be a bit finicky and slow-growing taking as long as 5 years to attain its full height and width.

This hybrid rose’s deciduous foliage is a deep, glossy green throughout the growing season.

Flowering & Fragrance

Osiria blooms throughout the summer and into the autumn. During the summertime, the blooms are deep fire engine red. They transition to darker red and white in the autumn.

The upper sides of the petals are red, and the center of the bloom is white. The undersides of the petals are also white.

This bicolor combination presents a stunning appearance, but not quite as dramatic as the Photoshopped images that are currently circulating online.

In addition to their visual beauty, Osiria’s blossoms are also deeply fragrant. This makes them a wonderful addition to patio or porch-side gardens as well as bouquets.

Light & Temperature

The sensitive, slow-growing rose Osiria likes full sunlight and a fairly sheltered setting. It can do well with northern, southern, eastern or western light. 

More light typically means more flowers, but you should expect limited flower production the first couple of years.

Rose Osiria is winter hardy in USDA hardiness zones 6b through 10b. Mulch deeply and provide good winter protection from the cold during wintertime.

Related Reading: Tips on How To Prepare Rose Bushes For Winter

Watering & Feeding

As with most roses, be careful not to overwater, and don’t allow the bushes to stand in water. 

Even so, you should provide a deep and thorough watering whenever the first couple of inches of soil surrounding the bush feels dry.

Use a high quality rose fertilizer very early in the springtime and again around midsummer.

Soil & Transplanting

Choose a planting site where no other roses have grown before. Work the soil deeply and amend it to be sure that it is well draining. 

Osiria roses can tolerate sandy, loamy, chalky or even clay soil, and any pH level, but you must be sure that the plant is positioned in such a way that excess water will drain off.

It’s best to dig a planting hole that is about twice the size and depth of the root ball and fill it halfway with a very high quality soil mixture.

Remove your Osiria rose from its original container and shake and brush the old potting mixture away from the roots. Position the plant on top of the soil mixture and backfill the hole.

Firm the soil mixture into the hole, and be certain not to make the soil level higher on the trunk than it was in the plant’s original pot.

Osiria Hybrid Tea Rose Grooming & Maintenance

Early in the springtime, before the plant begins to show new growth, perform a fairly aggressive pruning. Remove inner branches to ensure good air flow.

Throughout the growing season, deadhead spent blooms on a regular basis. Doing so will keep the plant tidy and will encourage more blooms. Keep on the lookout for powdery mildew and black spot.

Rose Culture: How To Propagate Osiria Rose Bush

Check your local garden center for potted Osiria roses. This is really your best option because you’ll be able to check out the health of the plant before you buy it.

There are many offers for seeds online, but anecdotal evidence indicates that this sort of purchase is hit-and-miss. 

Additionally, growing roses from seeds is rather challenging and may be even more so for these fairly finicky plants.

If you happen to receive a bouquet that contains an Osiria rose, try growing it as a cutting.

  • Clip the flower and trim the bottom part of the stem away.
  • Leave a couple of leaves in place. 
  • Dip the stem in a rooting hormone.
  • Put it into a pot of clean, well draining soil and keep it in a warm, consistently humid area with bright, indirect sunlight.
  • Alternately, you may wish to place a clear plastic bag over the cutting, and use artificial light if you need to.
  • Keep the soil slightly moist until new growth appears on the stem. At this point, you can begin treating your cutting as a mature plant.
  • If successful, this method may result in an Osiria rosebush, or it may result in whatever sort of bush the Osiria bloom may have been grafted upon. Either way, you’ll have yourself a new rosebush!

Osiria Rose Pests or Diseases

This hybrid is delicate and finicky, and many gardeners have expressed disappointment in it. When it does well, it has very beautiful and unusual blooms. 

However, the stems tend to be weak and often allow the blooms to droop. This is especially problematic after heavy rain.

The plant is also subject to all of the usual pests that plague roses, and it may be even more susceptible because of its hybrid status. You’ll need to watch out for:

This hybrid is also subject to the usual diseases that plague roses, including:

Generally speaking, the Osiria rose is not a good choice for beginning gardeners. If you have experience with roses, you can probably do quite well with it. 

Once it has passed the first couple of seasons, the plant tends to stabilize and improve in strength and performance.

Is The Rose Osiria Considered Toxic or Poisonous?

Roses are not toxic.

Is The Rose Considered Invasive?

This finicky hybrid is not invasive. 

Suggested Uses For The Osiria Rose Bush 

Anecdotal information indicates that this delicate plant really does best in a greenhouse setting, kept as a container plant with rich, high quality potting soil. 

When grown in the garden, Osiria is a good border plant. It makes a pretty addition to a cottage garden or a cutting garden.

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