While individual blooms last two to three weeks depending on light and weather conditions by deadheading the flowers as soon as they begin. Please leave a comment below and let me know Id love to hear from you. How To Care For Mums And Keep Them Blooming All Year Long Caring For Mums Fall Mums Hardy Mums Front porch with wooden seating and flowers. How long will mums last . The early to mid-spring is the best time to plant mums. Department of Agriculture zones 4 to 9. You can find hundreds of hardy varieties each with different colors and bloom shapes that will add interest in your autumn landscape. Some mums can survive well into the winter and perhaps make it to spring if planted at the right time and given the right care but even if the flowers die well established roots will regrow in the spring. Mums are not happy in extremely hot summer temperatures and may need to be shaded. Swelling in the salivary gland appears within hours or develops gradually over many days. ...