After the long May weekend, your back may be aching a little from gardening.  But experts say if you have a green thumb, you don’t have to give in to sore back muscles.  Doctor Stacy Irvine is a Toronto chiropractor.  She says warm up before you start gardening, by taking a short walk or a hot shower.  She says its going to make you feel better and you’ll probably enjoy gardening more.  But Irvine cautions, “it’s still possible to throw your back out because of repetitive motions and lifting heavy objects.”  She advises you switch tasks every 15 minutes and use knee pads when pulling weeds and planting.  Also, lift with your legs and keep your back straight.  Doctor Irvine says if you do get injured, try to see someone for treatment right away.  She says if you wait, it takes much longer to get back to feeling 100 percent.