Plum Tree Diseases: Identifying Silver Leaf, Rust and Rot
Most plum problems are one of six things. How to tell them apart by what the leaves, fruit and bark show, and which ones mean the tree is lost.
Diagnose and fix what is going wrong: pests, plant diseases, yellowing leaves, and the things eating your harvest.
69 guides
Most plum problems are one of six things. How to tell them apart by what the leaves, fruit and bark show, and which ones mean the tree is lost.
Dieffenbachia leaves turning yellow has 5 causes, and which leaves go first identifies it. Bottom leaves mean one thing, new growth another, patchy a third.
How to get rid of foxtails: the seed heads migrate into dogs and need surgery. Timing the removal to the 3-week green window, and what works after they dry.
How to get rid of leaf miners: the larva feeds inside the leaf, so contact sprays miss it. The 3 things that work, and why row cover beats everything else.
How to get rid of morning glory depends on which plant you have — annual or bindweed. Why digging makes 1 of them worse, and the method that exhausts the roots.
White fly on plants survives most sprays because 3 of its 4 life stages are armoured or hidden. What reaches each stage, and the 7-day cycle that decides timing.
Mosquitoes see poorly and hunt mostly by CO2, heat and smell. Vision only matters in the last metre — which changes what actually keeps them off you.
Dumping standing water and running a fan genuinely work. Citronella candles, bug zappers and dryer sheets mostly do not. Sorted by evidence.
Digging works in a weekend, chemicals take a year, fire is often illegal and rotting takes three. Here is what each one actually involves.
Workers are 3–6 mm and pale; swarmers about 10 mm with equal wings. The wing length and the antennae are what separate them from flying ants.
Sixteen spots in three rows and a coppery body means bean beetle. Ladybirds are rounder, glossier, and are not the ones eating your leaves.
Deer and some rodents respond to strongly scented soap. Mosquitoes do not. Here is what the testing shows and where the garden myth came from.
Darkling beetles do not bite or sting and mostly eat decaying matter. The larvae chew seedling stems, and in a poultry coop they are a real pest.
Carpenter ants excavate wood that is already soft and wet. They do not eat live wood, so they are a symptom of internal rot rather than its cause.
A hard spray dislodges most spider mites and raises humidity they dislike, but submerging a plant does not drown them. Repetition is what works.
Mulch itself does not breed mosquitoes — standing water does. Thick, compacted or waterlogged mulch creates the damp shelter adults rest in.
Neem oil kills powdery mildew spores it physically wets and prevents new infection for a few days. It does not cure leaves already badly colonised.
Neem oil smothers young squash bug nymphs on contact but slides off armoured adults. Timing to the egg hatch is what decides whether it works.
Smoke masks the cues mosquitoes hunt by and disrupts flight, which clears the area it covers. Step outside the plume and they are waiting.
Sulfur is a genuine contact fungicide that stops spores germinating on a sprayed surface. It is protective, not curative, and burns plants in heat.
A planted lavender bush releases almost no oil into the air. Crushing leaves on skin has some effect; a border of plants does not, at any number.
Barrier sprays last about three weeks, so services return every 21 days through the season. Draining water once weekly beats most of that schedule.
Only a systemic herbicide travels to the roots. Vinegar, salt and flame burn off top growth, which perennial weeds regrow from within a fortnight.
A selective broadleaf herbicide is the only product that spares lawn grass. Nothing kills weeds permanently — seed keeps arriving, so thick turf is the real answer.
Japanese beetles avoid a handful of plants, but nothing you grow repels them from the ones they like. Planting choice is avoidance, not protection.
A handful of plants contain compounds that deter ticks in a lab, but planted in a garden they do nothing. What works is habitat, not planting.
Worker ants ignore light and follow scent trails. The ants swarming a lamp are winged reproductives on a mating flight, and that is temporary.
A black spot at the blossom end, on the shoulder, or anywhere on the skin means three different problems with three different fixes. Position is the test.
Brown arborvitae foliage is often seasonal shedding, not death. Scratching the bark and checking where the brown sits separates the two in a minute.
Discarded wings on a windowsill and pencil-width mud tubes on foundations are the earliest termite signs — both appear long before visible damage.
Spider mite eggs are translucent spheres about 0.1 mm across, laid on leaf undersides in webbing. Here is how to see them and tell them from other specks.
Radishes pushing their shoulders out of the soil is how most varieties grow, not a fault. Here is when it is normal and when it means a real problem.
A chain that goes blunt in minutes has almost always touched soil, grit or bark dirt. Here is what actually dulls a chain and how to stop it happening.
A hose leaking at the tap, the nozzle or a joint is almost always a missing, flattened or wrongly seated rubber washer. Check it before anything else.
Smoke is unburnt fuel. Wet wood, a smothered fire and no air underneath cause nearly all of it, and each one is fixable in a single evening.
Lifting the edge of a brown patch tells you more than any photo guide: roots that hold, roots that lift, and grubs underneath mean three different causes.
Which leaves yellow, and whether the veins stay green, separates feeding from overwatering from squash vine borer. Work down the list in that order.
A bang when you shut the mower off is unburnt fuel igniting in the exhaust. When it happens tells you whether it is normal or something to fix.
Powdery mildew, dollar spot, frost scald and mower scalping all bleach turf white. Each has a test that rules it in or out in under a minute.
A romaine that shoots upward into a spire is running to seed, and the leaves turn bitter within days. Here is what triggers it and what to do now.
A gutter nest is awkward because you work from a ladder beside it. How to judge the risk, when to call someone, and the one thing never to do up there.
Japanese beetles have chewing mouthparts built for leaves and cannot break human skin. The pinch people feel is the grip of their leg spines.
Neem disrupts thrips rather than killing on contact, so it takes repeat sprays every 5–7 days. The pupae in the soil are what defeat most attempts.
Plant rust is a fungal disease of the order Pucciniales. Many species need two unrelated host plants to complete their life cycle.
Blight is rapid tissue death from fungal or bacterial infection — not one disease. What separates it from wilt, rot, spot and mildew.
Wilting in afternoon sun that recovers overnight is normal. Browning leaf edges, sudden collapse and bare stems each point somewhere different.
Small peppers are almost always heat stress, too much nitrogen, or a plant carrying more fruit than it can size. Each has a different fix.
Silvery patches along the veins are normal variegation on many varieties. A white powder you can rub off is mildew. The difference is easy to see.
Mushrooms mean fungi are digesting buried wood or thatch — a sign of healthy soil, not disease. They vanish on their own when the food runs out.
Marigolds have one well-evidenced effect: French marigolds suppress root-knot nematodes. The mosquito and rabbit claims do not hold up.
Basil, mint, lavender and clove genuinely repel flies — briefly, and at close range. Why removing the attractant beats any scent, and what works outdoors.
Mulch shelters insects rather than creating them, and most are decomposers doing the work. The few that matter, and how depth and placement fix them.
Five different pests look like white specks. How to tell mealybugs, whitefly, thrips, mites and springtails apart — and which one is harmless.
Not every shield bug is a problem — some eat the ones that are. How to tell the invasive brown marmorated from natives, and what to do about each.
What is diatomaceous earth doing when it works is cutting insect cuticles while dry. 3 rules cover grade, use and a dust mask. See whether it fits your pest.
Tiny jumping beetles that pepper brassica and eggplant leaves with holes. Why seedlings are the only real risk, and the controls that work in order.
Most lawns carry grubs harmlessly. The threshold is 6 to 10 per square foot — how to count them, and why timing matters more than the product.
Goat heads set seed within weeks and the burrs stay viable for years. Pull before it flowers, sweep up every burr, and never rotary-mow a mature plant.
Septoria, early blight, bacterial spot and late blight all start as dark leaf spots. Telling them apart decides whether you prune, spray, or pull the plant.
The adults are harmless; the larvae in the top inch of compost are what damage roots. Why letting the surface dry works, and what actually breaks the cycle.
Late blight destroys a plant in days and there is no cure. How to identify it against early blight, act fast enough to save the fruit, and prevent it next year.
Citronella, lavender and peppermint all repel mosquitoes in a lab. Almost none of it survives contact with a real backyard — here is what actually reduces bites.
The right dilution, why it needs soap to mix, when to spray, and which pests it works on. Neem is slow and specific — treat it as a knockdown and it fails.
Pillbugs are decomposers that eat decaying plant matter — but they will graze seedlings and soft fruit when the population gets high and the ground stays damp.
Does vinegar kill weeds down to the root, or only the leaves? Only the leaves, and 4 checks cover strength, gear and perennials. See where it earns use.
Powdery mildew is the one fungus that does not need wet leaves — it thrives in humid air and dry foliage. How to spot it early and what treatments hold up.
Tomatoes split when a dry spell is followed by heavy water — the inside grows faster than the skin. How to read the crack, and how to stop it happening.
Plants that repel mosquitoes barely work unless you crush the leaves. 4 measures compared, starting with standing water. See which suits your yard.
Most curling tomato leaves are harmless leaf roll from heat or water stress. A few causes are serious. Here is how to tell them apart in under a minute.
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