The Dreaded Black Spot, Scourge of a Rosebush Life

This blog post is one of (I'm sure!) many I'll write in the near future, so if I don't cover something, shoot me a message, and I'll do a blog on it.

Roses.  I love them, but I've almost given up on roses several times because of the horrible infestations of Black Spot that my poor bushes would endure year after year.  At one point, I had 54 bushes, all types of roses, and I spent some serious money on hybrids and disease resistant breeds.  I hated seeing the first indication of Black Spot because I knew if I didn't spend a couple of hours a day hand-picking the leaves, then it would spread faster than butter in July.  You have to love roses to put up with their weakness to disease (and don't get me started about Japanese beetles).

Through the years, I found more than half a dozen sworn-by-the-expert cures but none of them truly worked with 100% efficiency and several made a serious dent in the checkbook.  And I've also discovered that weather can really be your enemy when you're trying to treat Black Spot.

There are a couple of things that have worked for me during the years, and one of them that I would normally recommend is something I just discovered is extremely toxic to animals, so I'm leaving that one off my list of suggestions.

Because the disease is spurred on by heat and humidity, Black Spot usually happens during the height of summertime, which means you get to enjoy your roses for about a month (where I live) before you see the first telltale signs.  If you know you might have the disease in some existing roses, it's a great idea to treat before you see the slightest signs of the disease.  Prevention includes making sure that the space where your roses are planted is clean of debris and that the roses have plenty of sunlight and breathing space.  If the bushes have grown since first planted and are now touching each other, Black Spot will spread like . . . well, the plague.

So, preventing Black Spot:

• Plant roses at least 24" apart in holes that are three times the size of the root ball.
• Ensure roses get sunlight most of the day and that they are watered regularly (Note:  everything can be argued, and I'm sure my sister will tell you that the roses she has out behind her house facing a very busy highway have been very successful thriving without any human help whatsoever).
• Keep the ground around the roots of the plant clean of dead leaves and debris (Black Spot moves into the plant when the spores on the ground connect with the rose via ground water).
• As soon as the bush starts to leaf out, spray the bush with a Baking Soda Spray (1 tsp baking soda, 1 quart water). Add a couple of drops of non-bleach detergent to the mix so that the baking soda will stick to the leaves.
• Make sure that every leaf is sprayed, top and bottom.
•  If the Baking Soda Spray doesn't work, check with the local greenhouse for Neem oil.
• Watch the plants and clean, water, treat them at least every week, preferably every four days.
• Caveat:  Some gardeners swear by a very strong fungicide, and you might want to try that, too, but I've tried to deal with this issue as naturally as possible.

Throughout the summer, continue this prevention program and make sure you trim/prune your bushes regularly so that you'll keep this disease (and others) at bay.

The point is to get roses that look like this:

~~~***~~~   ~~~***~~~   ~~~***~~~   ~~~***~~~   ~~~***~~~   ~~~***~~~   ~~~***~~~

And this post's poem is, of course, about the beautiful rose.

'Asking for Roses' by Robert Frost

A house that lacks, seemingly, mistress and master, 
With doors that none but the wind ever closes, 
Its floor all littered with glass and with plaster; 
It stands in a garden of old-fashioned roses. 

I pass by that way in the gloaming with Mary; 
'I wonder,' I say, 'who the owner of those is.' 
'Oh, no one you know,' she answers me airy, 
'But one we must ask if we want any roses.' 

So we must join hands in the dew coming coldly 
There in the hush of the wood that reposes, 
And turn and go up to the open door boldly, 
And knock to the echoes as beggars for roses. 

'Pray, are you within there, Mistress Who-were-you? ' 
'Tis Mary that speaks and our errand discloses. 
'Pray, are you within there? Bestir you, bestir you! 
'Tis summer again; there's two come for roses. 

'A word with you, that of the singer recalling- 
Old Herrick: a saying that every maid knows is 
A flower unplucked is but left to the falling, 
And nothing is gained by not gathering roses.' 

We do not loosen our hands' intertwining 
(Not caring so very much what she supposes) , 
There when she comes on us mistily shining 
And grants us by silence the boon of her roses. 

Deadheading Primroses

Recently, I experimented with various  plants in order to determine which would be a healthier plant if I did some old-fashioned deadheading.  Some worked well; others didn't.  I thought it might be a good idea to share info about primroses with those of you who love them as much as I do.

Primroses (Primula polyanthus) are an old-fashioned perennial that have enjoyed popularity for hundreds of years.  They are native to the Northern Hemisphere.  Over 400 species of the rosette-like plant exist both in the wild as well as cultivated in proper gardens, and one of the tricks primrose gardeners learn early is that their primrose bed will last much longer is properly deadheaded.

Deadheading Primroses

Tip: Make sure to sterilize your scissors or pruning shears before using them to deadhead your primroses.

Deadheading simply means grooming the plant. By removing the spent flower, you prevent your plant from going to seed, and allow it to mature. Cutting back the spent flower stems also encourages new growth, so you'll see fresh flowers. Once your plants have started to thrive, a simple walk around the garden several times a week allows you to see how your primroses are progressing and whether you might need to clean up the flowers that are spent.

·        Start checking your garden in late spring.

·        Carry a pair of scissors or a small pair of pruning shears in your pocket for the task. Some gardeners prefer to simply pinch away the spent flower between thumb and forefinger, but a set of scissors makes it easier to snip away the dead flower/leaves.

·        Wear rubber gloves since some people might be allergic to certain varieties of plants. It also curbs the spread of disease if your naturally oily fingers are protected. Certain floral diseases easily spread when our fingers flit from one flower to another.

·        Look for the flowers that have begun to fade or are drying out.

·        Reach down to the base of the flower stalk and hold the dead flower gently.

·        Bend the flower to expose the stem, then either pinch or snip the dead flower away from the plant.

·        It's a wise idea to carry a small bag or wear an apron and drop the dead flower in the bag/apron rather than on the ground. You can dump your deadheaded materials into a recycling pile when you're done with your task.

·        Because too much water will rot primroses, check them occasionally and clip off any yellow or rotten lower leaves you see around the base of the plant. Removing rotten leaves promotes new growth. Your primrose bed might seem a bit droopy after you deadhead and trim old growth, but you will be rewarded when new buds start to arrive.

·        If primroses get too wet, they can develop conditions like crown or root rot and garden bugs, like aphids or spiders, may attack the plants.

Once your plants stop blooming, pull the primroses from the ground or your pots and put into containers until fall. The best soil is gritty and humus-rich. Keep your containers in a sheltered spot and keep the plants moist but not wet.

Growing Primroses

You can grow primroses from seed or purchase your plants from a grower.  If you choose to grow them from seed, be aware that the seeds are exceptionally small and it is difficult for the novice gardener to be successful starting these plants from seed.

Most primula varieties flower reliably and are easy-to-grow. Plant them in sun or partial shade and make sure to choose an area or pot that provides good drainage.  Primroses don't like to be wet!  If you can shelter them, you'll have very happy plants.

Offering your plants liquid fertilizer every 2 weeks or so will encourage them to produce fresh buds and create a beautifully flowering plant. 

Varieties

Most of the 450+ species of the genus primula like cooler weather and will not tolerate midsummer heat. They come in every color of the rainbow and the species names span the alphabet.

The varieties are distinguished by their rosette of leaves that resemble the leaves of a head of lettuce. In the center of the rosette are the flowers. Each flower has five petals joined at the base.  Flowers appear on leafless stalks. Common colors include white, red, blue, yellow, purple, and cream, but some species also produce bi-colored flowers.

THE POEM

Many poets have written about the beauty of primroses, but this one is my favorite:  

"My Primrose" by Joseph Horatio Chant

My sweet primrose with thy open face,
And with fringe-like leaves, without a trace
Of coarseness, either in flower or stem,
Among all my plants thou art the gem.

My lovely lilies soon disappear;
Thy bloom is constant through all the year;
In summer's heat and winter's cold,
Undimmed the light of thy floral gold.

Or if thy color be pink, or blue,
Or white as snow, thou art ever true;
My room is bright with thy smiling eyes,
And thy fragrance rare I also prize.

Thou hast done thy part, my little pet--
Let me keep thy roots forever wet,
But guard with care all thy tender leaves
And growing crown, which the earth-crust heaves.

Thou dost heaven-ward tend, aspiring high,
To kiss the stars in the vaulted sky,
And they look down from the azure blue,
My sweet primrose--they are smiling, too.