Q.Failure To Grow – Russian Sage
I have 15- 6 year old Russian Sage bushes, they have never gotten over 10 or 12 inches high. I put 1 cup of 10-10-10 around them each spring and mulch them with pine needles when needed. I read that they don’t need much water but I have tried more water, less water and they will still do not grow.They are planted in mostly full sunlight. Any suggestions?

Certified GKH Gardening Expert
Is it possible you have a dwarf variety? Many retailers prefer the shorter varieties that don't flop over. Try only fertilizing every other year. And cut back on the water.
Here are the ideal growing conditions, which may help:
https://www.gardeningknowhow.com/ornamental/flowers/russian-sage-flowers/russian-sage-care.htm