Actually roses love both bananas and
Are your bananas turning spotty and black? Don't throw them away; give them to your roses. Bananas are a natural source of potassium that help roses to thrive. You can feed them to your roses in several different ways.
Banana peels contain many useful nutrients, including calcium, magnesium, sulfur, phosphates and sodium. The peels rot quickly, which means these nutrients are readily available to the plant.
You can use both the banana and the peels...mostly I use the peels, keeping them in a sealed container until I have several...I cut them up roughly and put a handful into the soil next to each rose bush. I have also emulsify old bananas and peels in my blender with water. I pour this on the base of the rose bush. I warn you it looks nasty but roses love it.
In addition to planting the peels, if you have aphids, try tossing a peel or two on the bush...chases the aphids away...after they are gone, plant them next to the bush.
Epsom salts are a naturally occurring mineral. This inexpensive household product is magnesium sulfate which may increase chlorophyll production and help plants use phosphorus and nitrogen better. Epsom salts makes the foliage greener and more lush, it produces more canes and more roses. I use 1/4 cup sprinkled into the soil around the rose, and watered in well, both in the spring and the fall.
For ongoing rose care, mix 1 T. of Epsom salts per gallon of water and apply as a foliar spray.
Don’t worry about being exact as to when you apply the Epsom salts. This is a home gardening remedy and there are as many formulas as there are home gardens. Some gardeners only add Epsom salts at planting time. Others like to water or foliar feed with Epsom salts every other week. And some gardeners simply use the Epsom salts when they remember. It’s all good.
And of course don't forget to toss some Epsom Salts into your bath after a day in the garden...great for soothing those aching muscles.