Black Spot — Rose Fungus Disease

Is it a Deadly Disease for my Roses?

Black spot on roses not only mars the beauty of
your rose shrub, but if this rose disease gets out
of control, it can defoliate your roses totally.
Black spot fungus can, thus, weaken your rose
plant
and cause its demise.
Black spot disease, a common rose care problem,
thrives
in humidity and is contagious to other
roses.  Fortunately, simple rose gardening main-
tenance
practices and some natural and low toxin
rose fungus remedies
can help prevent and treat
this ugly rose malady
and control its devastation.

 

Away Black Spot!

Well..Shakespeare I’m not…but is my point made?  :-)
  

Seriously, black spot can smudge up the looks of your rose in no time. It’s not just the look that is troublesome, however. If this nasty fungus gets the upper hand, it can defoliate your wonderful rose, and weaken your shrub as a consequence, potentially leading to the demise of your delightful floral friend. Additionally, if one rose shrub becomes infected with black spot fungus, your other roses may follow suit, since black spot is contagious for other roses. You could end up with a garden full of ‘naked ladies’…and that is not a plus!

Black spot looks like it sounds. (the scientific moniker is ‘Diplocarpon rosae’ ) Round black blotches show up on the rose leaves, often surrounded by a yellow halo, and the leaves themselves may turn a yellowish color. Sometimes you may even see some purple-red hued spots appear on the canes and stem as well.. Keep in mind that it doesn’t take long — only around 6-7  hours of warm, moist conditions to bring the disease spores to ‘life’, and the ‘uglies’ will begin to show up in 3 to 10 days.

                              Black Spot not only mars the 
                          looks of your rose shrub,

Black spot rose disease

   but this rose disease can totally 
   defoliate and weaken your roses
   if left untended


Black Spot rose fungus loves and thrives on humidity and moisture. Black Spot disease is one reason to water your roses only from the bottom and not from above. Any moisture that is not evaporated from the leaves and stems on your rose shrubs during the day is akin to a welcome mat for the spores of this unwelcome intruder. They need moisture on the surface of leaves to germinate and grow.

Hybrid Teas seem to suffer more easily from black spot. With sturdier varieties produced each year, this may not hold true for all, but as a general rule of thumb, if you favor such rose plants, prepare in advance to protect your rose flowers to be safe.

Humid regions, in particular, are prone to this fungus disease, so a regular pre-season strike regimen is strongly recommended for your roses, along with regular control methods during the growing season. In areas where regular humidity is not a problem, periods of unusual heat and humidity and extended rain days are experienced, and this dastardly disease is likely to take residence and we may inherit an ongoing battle.

    So, what to do about the Dastardly Black Spot Rose Problem?

In areas where you can’t control the humid climate, planting disease resistant roses is recommended for happy rose gardening. Old Garden/Antique/Heritage roses as well as the Species and newer Knockout roses are hardy specimens known for pest and disease resistance. Again, Hybrid Teas in general will have a harder time and require more of your attention to keep them protected.

There is a rich array of choices in the older roses, providing ample selections for color and bloom, so no need to despair. They bloom usually in late spring, with intermittent displays later through summer. And that is not to say that you can’t grow Hybrid Teas; it’s just that you’ll likely need to spend more time in their nurture and protection in this circumstance. There are likely other resistant rose shrubs you can easily grow in your region as well; consult your local nursery for the best choices.

Black Spot on roses can be combatted in simple ways. As with all rose plants, prime importance is given to some simple rose management basics. The best medicine for black spot, as with any disease, is prevention when possible. Know your weather conditions, any weakness of your particular rose shrub friends, and be combat ready.

                      Welcome Home THESE Gorgeous Rose Beauties
to Your Home Rose Garden!

                      Beautiful AND Black Spot – Disease Resistant!

(mouse over or click for more info)

 

    Prevention and Disease Combat for your Roses

Along with choosing the most disease resistant rose types for your area, put into place these management practices to help your roses.

 

  • Allow air to circulate and light to penetrate.

You might memorize that as a ‘sing-song’ to remind yourself of these basic needs for all your glorious rose companions.

Place rose plants at enough distance from one another and other plants to allow for air and sunlight, usually about 3 – 4 feet apart, depending on how large the rose bush will be at maturity. Plant your roses far enough away from trees and shrubs to accomplish the same. Additionally, some distance from trees and larger shrubs will help keep your roses from competing for nutrients in the soil, as well as keep them from being too shaded, and thus, lacking enough sunlight to flourish.

Prune your roses to the recommended open ‘V’ shape to allow for proper air circulation and sunlight. If your roses are already established, eliminate anything that may crowd your rose shrubs, transplanting other plants or fellow roses to create more ‘breathing space’ for all.

  • Water at the rose’s base, not from above whenever possible.

Use a soaker hose or drip hose to make things easier on yourself and your beautiful roses. Be careful of splash up on the leaves from the ground as well. If the moisture cannot be dried during the daytime, your rose shrub is being set up for black spot infestation. If you must water from above, do so in the morning to give your roses maximum time to dry off. Using mulch and keeping fallen petals, buds and leaves cleared away will help as well.

  • Sanitation

Keep all rose debris beneath a rose bush cleared away, as disease spores of many types can grow on this and survive the winter as well! If your rose is infected with black spot, remove affected leaves on the plant and those that have fallen and discard this debris by placing it into a plastic bag that is sealed shut or into a garbage can. Do NOT put this matter into a compost bin! (Don’t put anything diseased into a compost bin…) The disease spores will not be sufficiently destroyed, and you’ll reintroduce them when applying the compost!. Cutting back the affected canes is also a good idea, disposing of them appropriately as well. Proper clean up will help minimize further infestation of this rose as well as others.

 

    I’ve Been Good – Done All That — Why Do My Roses  STILL     Have Black Spot?

 

All the above being said… sometimes no matter what we’ve done…Black Spot disease will still strike our beloved roses.  Mother Nature’s whims with humidity, extra wet conditions and sticky weather will do their damage to our blooming  rose garden treasures. It is Still necessary to maintain your roses as described previously as basic, wholesome maintenance. But sometimes, our best efforts will go unrewarded and not keep Black Spot totally away…but certainly… the disease infestation will not likely be as bad as had we not done our due diligence. We and our roses remain at the mercy of nature..and we can only do so much to outwit and outwork it. So…the most successful of rosarians will need to deal with Black Spot from time to time..and maybe more than that. We will just have to learn to tolerate a bit of  Black Spot when conditions are beyond our control.

 

The important thing to remember is not to let it get out of hand. If the infestion is hitting early on…get cracking and do what you can to combat it. If the roses have bloomed nicely and the season is winding down, we may be able to tolerate a bit more black spot. But  CLEAN UP is STILL essential to avoid it lingering through the winter to strike again with vengeance in the spring.

 

Admire your roses and while you visit, pick away what you can of any infected leaves and/or stems. Then sit back, overlook a few spots ..and enjoy the beauty you have created for all of nature, human and otherwise …to appreciate!

 

 

For MORE tips on Battling Black Spot…Read On …!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

       - Rose Shrubs - Gardening Roses - Rose Gardening Inspiration for Everyone! -