|My rose bush leaves are turning yellow. Is there any food or fertilizer I can give them?|
|Yellow leaves can be caused by many things including lack of nitrogen, insufficient light, water-logged soil (plant roots need oxygen to thrive), dry soil, or iron deficiency. If the older bottom leaves are yellow, but new growth is green, it's usually a lack of nitrogen. If new leaves are yellow, with green veins, it's usually a lack of iron. (Lack of nitrogen is a more common problem than lack of iron.) Soil should be kept moderately moist (but not wet). Finally, transplant shock can contribute to yellowing. If new growth shows up as green, that might be the problem. Try to isolate each of these possibilities one at a time to determine the problem.
Nitrogen, phosphorous and potassium are the 3 major nutrients for all plants. (They correspond to the 3 numbers on fertilizer packages.) Nitrogen promotes growth of green leaves. Roses are heavy "feeders" during their bloom period. If you decide the other issues aren't the problem, I suggest you apply a rose fertilizer. The second and third numbers on the package should be higher than the first. The thing to avoid is feeding them with a too-high-nitrogen fertilizer that will encourage foliage growth at
the expense of flowers. Keep them consistently moist and mulch with 2-3 inches of compost to help maintain soil moisture. Rosarians I know fertilize their roses every 6 weeks during the blooming season. You can also apply a slow-release fertilizer that will feed your roses over a longer period of time. I hope this info helps.