Answer: Onions or chives are sometimes planted near roses in an effort to repel aphids, but I have not heard of using them specifically as fertilizer. Roses usually do well in full sun and in average or better soil that is well drained, meaning not saturated or sopping wet. An annual application or two of good quality compost and a general purpose slow release fertilizer such as 10-10-10 applied in early spring and early summer -- per the label directions -- should be sufficient. Read and follow the label instructions. Using an organic mulch also helps feed the soil as it breaks down slowly over time. You could certainly use onions or onion tops as one of the many different ingredients in your home made compost if that is something you are interested in. If you would like to develop more specific fertilization program for your roses, I would suggest you work with your local county extension to run some basic soil tests and then work up a plan based on the test results. Good luck with your roses!
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