Pre-emergent

Can you re-apply a pre-emergent, once shrub roses are blooming? Have black/brown spots on leaves and leaves look like something is eating on them.

1 Comment (Open | Close)

1 Comment To "Pre-emergent"

#1 Comment By Downtoearthdigs On 05/30/2017 @ 8:20 am

I would give the rosebushes a treatment of Bayer Tree and Shrub Granules per the label instructions for Ornamentals/Roses. It is a systemic disease control product and has some food in it too so that it helps strengthen the bush to help fight the disease attack. A pre-emergent usually refers to an herbicide which is not what is wanted here, so I am assuming that you mean a systemic. Yes you can reapply systemics once blooming has started. If the rosebushes turn out to have black spot fungus attacking them, you may need to spray them with a product called Mancozeb, it is available on Amazon.com and will stop most black spot attacks in their tracks.

Article printed from Gardening Know How Questions & Answers: https://questions.gardeningknowhow.com

URL to article: https://questions.gardeningknowhow.com/pre-emergent-3/

Have any questions about this topic? Visit us at https://questions.gardeningknowhow.com to ask your questions and get friendly answers from gardening experts.

You can also find us at:
'Like' us on Facebook: https://www.facebook.com/gardeningknowhow
Follow us on Twitter: https://twitter.com/gardenknowhow - @gardenknowhow
Follow us on Pinterest: https://pinterest.com/gardenknowhow/