The MGS Forum

Gardening in mediterranean climates => Pests and diseases => Topic started by: Daisy on July 23, 2011, 07:40:12 AM

Title: Yucky roses
Post by: Daisy on July 23, 2011, 07:40:12 AM
Does anybody know what is wrong with my rose Duchess de Brabant?
She was the first rose I planted, about 16months ago. She has grown well, and does not have any rust or mildew.
However, most of her blooms are manky and brown. Not all of her buds open and the ones that do look awful.
Occasionally, she can produce a perfect bloom, but not often.

(http://i567.photobucket.com/albums/ss112/daisyincrete/024-1.jpg)

(http://i567.photobucket.com/albums/ss112/daisyincrete/026.jpg)

Daisy
Title: Re: Yucky roses
Post by: Alisdair on July 23, 2011, 07:58:02 AM
Could the blooms of this beautifully scented rose be getting wet overnight and then overheated in the sun? These very double flowers are highly susceptible to that sort of thing.
Title: Re: Yucky roses
Post by: Daisy on July 23, 2011, 08:37:49 AM
That could be the case possibly in winter or spring, when there is some moisture in the air. But we haven't had rain since May.
The Duchess is watered once a fortnight and only at the base.
These photos were taken about two weeks ago.
Daisy :)
Title: Re: Yucky roses
Post by: David Bracey on July 23, 2011, 09:09:19 PM
Your manky roses could be showing an early attack of Botrytis.  This fungus occurs in many forms and will prevent rose buds from opening.

Two insect pests which also cause this problem are thrips and midges.  Look for holes at the base of the buds and knock the buds to see if any thing falls out. David
Title: Re: Yucky roses
Post by: Daisy on July 24, 2011, 06:06:56 PM
David, I have just been out to peer even more closely at my manky roses. You are right. There are tiny holes at the base of the bud.
When I opened the bud, I could see tiny insects.
They are too small to make out any detail.
I must admit I didn't expect insects. Why would they only be on just the one rose?
Because I have such a tiny garden, all my roses are close to each other. The Duchess has had this problem since she first bloomed, but none of the other roses have.
Any ideas what I can do about it?
Daisy :)
Title: Re: Yucky roses
Post by: David Bracey on July 24, 2011, 08:44:47 PM
Daisy are your roses manky or yucky? or both?  The insects are probably thrips...very small...............there are several options ......do nothing and live with the problem..............remove the infected buds early....or spray with an insecticide.  Pyrethrum would probaly do the trick or there is another natural product ............"Neem" the active ingredient is azadirachtin which has become popular relatively recently. You can read more on-line.  Let me know how you get on David
Title: Re: Yucky roses
Post by: Daisy on July 26, 2011, 03:27:28 PM
David. The roses are definitely both. ;D ;D ;D

I will have to try the pyrethrum or azadirachtin, as the poor roses have had this problem since first flowering.
The only other solution, would be to dispose of her.
That would be a shame as she flowers for most of the year.
Daisy :)