Stems and petioles

Hemp russet mites: the pest you can’t see Upward-curling leaf edges and a dull, bronzed look, with no webbing and no bugs you can find, may mean russet mites. They're… Aphids: clusters and sticky leaves Clusters of small soft insects on stems and under leaves, often with sticky or shiny residue, mean aphids. They can be knocked… Powdery mildew: white dusty patches on leaves White, flour-like spots on the top of leaves are usually powdery mildew. Remove affected leaves early, because new spores can appear every… Bud rot: brown, dying buds and gray fuzz A browning, dying section of bud, sometimes with gray fuzz, usually means bud rot. It can't be cured and it often starts… Root rot: brown roots and a plant that keeps declining Wilting or stunting that watering and feeding don't fix, with brown or decaying roots, points to root rot. Check the roots before… Purple stems and petioles: the phosphorus myth Purple stems are not a reliable sign of phosphorus deficiency.