The rose section of the nursery is absolutely stunning at the moment, the additional rainfall this spring has allowed them to develop lovely full flower buds.
These Pierre De Ronsard roses are a highlight at the moment. This variety is commonly grown as a climber, but this example is a weeping standard. I have also seen Pierre De Ronsard kept pruned as a shrub rose.
In addition to pink, there is also a blushed white variety called 'Blushing Pierre' and a red version called 'Red Pierre'. All three varieties feature a similar bloom structure and overall growth habit, I prefer the red and pink versions though.
That added rainfall, now teamed with warmth, means there is an added challenge - blackspot. Fungal problems thrive in humidity, blackspot is no different. This situation is not helped by our overhead watering system and the sheer volume of rose stock we have this year, limiting airflow. Even with weekly sprays with both Mancozeb and Triforine, the blackspot is still developing. It can be hard to explain that to a customer, that blackspot and roses go hand in hand, even with the best practice treatments.
If you are also battling blackspot on roses, here are a couple of things to consider trying -
-Maintain airflow by pruning out inward pointing shoots. This helps keep the middle of the bush open and improves airflow.
-Avoid overhead watering, directing water to the root system rather than over the foliage.
-Thin out your mulch a little around the base of the plants. Mulch is great, but it can also increase humidity.
-Remove fallen blackspot affected foliage as best as you can. This will limit the spores being released back onto the rest of the plant. It's also a good idea to put this material in the bin rather than the compost to avoid spreading the spores around the garden.
-Regularly use an appropriate fungicide. Triforine is the best, but Mancozeb can be added into the rotation as well. There are also homemade remedies, but their effectiveness is limited. You can also get combined insecticide/fungicide products for roses, but I prefer to treat blackspot with a dedicated fungicide for a more focused effect. Both Triforine and Mancozeb are systemic, meaning they have a residual effect for 10 - 14 days.
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