Hi, I bought a mint plant from Walmart, figuring I can repot it and make it grow bigger. However it just keeps growing taller. I have 6-7” of just stem, with leaves on top. How/where should I trim it to make it bushier/fuller please?
I agree with both previous answers - your mint needs a lot more daylight. that's why it's getting tall and lanky, shortage of light. They really prefer full sun but also grow well in partial shade (so half a day's sun). Find a bigger pot with drainage holes, only one size bigger, move it into that using fresh potting soil, water it well and allow to drain down freely. Then cut it down to about 2 inches and stand in well lit place, like a windowsill with good daylight and preferably some sun. Water when the surface of the soil feels just about dry to the touch, water thoroughly and empty any outer tray or pot after 30 minutes so it's not left sitting in water.
I also would suggest you upgrade the plant to a bigger pot (one size bigger) or put it in the ground if possible--not sure if this is an options for you. The plant is most likely root bound and there is probably a lack of nutrients in the soil. Lastly a bit of sunlight would help as in the previous comment. Mint likes partial shade to full sun. Good luck!