Why are the bottoms of all my tomatoes going black?
Our Advice
This disorder is called blossom end rot and is caused by erratic watering, calcium deficiency or both. Treat the plants with calcium nitrate at 50g (1.75 ounces) in 5 litres (1 gallon) of water. This will not cure the affected fruits but will help to stop newly-forming fruits being damaged.
Ask Another Gardening Question
Not what you were looking for? If you can't find an answer on the website, you can contact our experts directly and we'll do our best to help.
Learn More About Pests & Diseases
Angle shades moth
Anthracnose
Box blight
Box tree caterpillar
Canker — Bacterial
Canker — Bleeding
Canker — Fungal
Capsids
Centipedes
Chafer grubs
Coral spot
Cutworms
Earthworms
Earwigs
Eelworms (leaf & stem)
Eelworms (soil-borne)
Froghopper
Fuchsia gall mite
Garden Ants
Grey mould
Honey fungus
Leaf cutter bees
Leaf Rolling Caterpillars
Leaf spots — Fungal
Leatherjacket
Lily beetle
Mealy bugs
Mildew — Downy
Mildew — Powdery
Millipedes
Pear midge
Phytophthora root rot
Rose Black spot
Rusts
Sawfly — Berberis
Sawfly — Gooseberry
Scale insects
Sciarid flies
Slugs
Snails
Sooty moulds
Thrips
Vine weevil
Whitefly
Wireworms
Woodlice
Woolly aphid