Diseases

Every disease the plant guides share, with the plants it hits and the timing that matters.

50 diseases290 plants covered so farlargest: root rot · 73

Most widespread first

73 plantsRoot RotMostly houseplants · Lamiaceae 1059 plantsPowdery MildewMostly perennials · Asteraceae 1234 plantsRustMostly perennials · Poaceae 524 plantsLeaf SpotMostly shrubs · Aquifoliaceae 321 plantsCrown RotMostly perennials · Ranunculaceae 317 plantsAlternaria Leaf SpotMostly annuals · Brassicaceae 1017 plantsDowny MildewMostly annuals · Brassicaceae 416 plantsVerticillium WiltMostly trees · Solanaceae 415 plantsDamping OffAll annuals · Solanaceae 413 plantsBotryosphaeria CankerMostly shrubs · Ericaceae 313 plantsMosaic VirusMostly annuals · Solanaceae 413 plantsWhite MoldMostly annuals · Fabaceae 311 plantsAster YellowsMostly perennials · Asteraceae 611 plantsCedar-Apple RustMostly trees · Rosaceae 910 plantsAnthracnoseMostly trees10 plantsBacterial Leaf SpotMostly annuals · Rosaceae 310 plantsBacterial Soft RotMostly annuals · Solanaceae 310 plantsClubrootMostly annuals · Brassicaceae 1010 plantsFrost DamageMostly annuals · Solanaceae 310 plantsRoot Knot NematodesMostly annuals · Solanaceae 39 plantsSalt BurnMostly houseplants · Asparagaceae 39 plantsSeptoria Leaf SpotMostly perennials · Asteraceae 39 plantsSouthern BlightMostly annuals · Solanaceae 39 plantsWinter BurnMostly trees · Cupressaceae 38 plantsBotrytisMostly annuals · Asteraceae 28 plantsBrown RotMostly trees · Rosaceae 88 plantsCrown GallMostly trees · Rosaceae 58 plantsCytospora CankerAll trees · Rosaceae 48 plantsPurple BlotchMostly perennials · Amaryllidaceae 87 plantsApple ScabMostly trees · Rosaceae 57 plantsBacterial Leaf ScorchAll trees7 plantsBlack RotAll annuals · Brassicaceae 77 plantsCercospora Leaf SpotMostly annuals · Amaranthaceae 37 plantsEdemaMostly annuals · Crassulaceae 37 plantsFusarium WiltMostly annuals · Cucurbitaceae 27 plantsPhytophthora BlightAll annuals · Cucurbitaceae 47 plantsTomato Spotted WiltAll annuals · Solanaceae 47 plantsTransplant ShockMostly shrubs · Ericaceae 36 plantsBlack KnotMostly trees · Rosaceae 66 plantsBlossom End RotAll annuals · Cucurbitaceae 36 plantsCurly TopAll annuals · Amaranthaceae 36 plantsFireblightMostly trees · Rosaceae 66 plantsLate BlightAll annuals · Solanaceae 66 plantsSooty Blotch and FlyspeckMostly trees · Rosaceae 56 plantsSunscaldMostly annuals · Cucurbitaceae 25 plantsEarly BlightAll annuals · Solanaceae 55 plantsHerbicide DriftAll annuals · Solanaceae 45 plantsPeach Leaf CurlAll trees · Rosaceae 45 plantsPhomopsis BlightMostly trees · Cupressaceae 35 plantsShot HoleAll trees · Rosaceae 5
Photo credits — 106 images

Timing only — the label is the law

This page tells you when to watch for a disease and when treating is worth considering. It is not a recommendation to apply any particular product. Read and follow the product label before you spray — under federal law the label is the legal instruction, and using a pesticide against it is illegal.

  • Check the pre-harvest interval. Every product that’s cleared for an edible crop sets a minimum number of days between spraying and picking. Find it on the label before you spray anything you intend to eat.
  • Check the re-entry interval before you or anyone else works in the treated area again, and use the protective equipment the label names.
  • Confirm the product is registered for your crop in your state. This page groups many different crops together, and a product legal on one of them is not legal on all of them — state registrations differ too. Your state pesticide agency or local extension office can confirm both.
  • Rates and mixing instructions come from the label, never from us. We don’t publish them because they differ by product and formulation.