Plants that are poisonous to cats

Aconite (Aconítum) — systemic toxic effects. All parts of the plant are poisonous.
Amaranth (Amaránthus) — systemic toxic effects.
Amaryllisic (Amaryllidáceae) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency. When ingested, cause damage to the nervous system, some cause allergic dermatitis.
American Lysikhituum (Lysichiton americanum) — causes diarrhoea and vomiting.
An orange tree, aka a bitter orange, bigardy (Citrus aurantium) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Anthurium Scherzer (Anthurium scherzerianum) — can cause swelling of the mouth.
Apricot (Prúnus armeniáca) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Arizema trifoliate (Arisaema triphyllum) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Aroid (Araceae) — aglaonema (Aglaonema), calamus (Alocasia), amorphophalus (Amorphophallus), anthurium (Anthurium), dieffenbachia (Dieffenbachia), zamiakulkas (Zamiaculcas zamiifolia), caladium (Caladium), monstera (Monstera deliciosa), Sauromatum (Syngonium), spathiphyllum (Spatiphyllum), Epipremnum (Scindapsus), philodendron (Philodendron), etc.) — juice contains oxalic acid, causes burns, can lead to collapse.
Asclepiadaceae (Asclepiadáceae): Stapelia (Stapelia), waxy ivy, or Hoya fleshy (Hoya carnosa), etc. — various manifestations.
Asparagus — flowerbus (Asparagus plumossus), Sprengeri (Asparagus densiflorus sprengery) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Azalea (Azalea) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Biota (Biota orientalis), or thuja east (Thuja orientalis) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Boxwood evergreen or Buxus (Búxus) — systemic poisoning, even death.
Buttercups (Ranúnculus) — systemic toxic effects.
Caladium two-color (Caladium bicolor), or marble (Caladium marmoratum), colored (Caladium picturatum), (Caladium hortulanum) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Callas (Calla) — contain oxalic acid, cause swelling of the oral mucosa, can lead to collapse. Calla ethiopian (Calla aefiopica) aka Zantedesky Ethiopian (Zantedeshia aethiopica) — causes impaired motor coordination and acute heart failure.
Chlorophytum (Chlorophytum) — causes allergic dermatitis, but not all cats.
Chrysanthemum (Chrysanthemum) — causes oral dermatitis, allergic dermatitis. Causes vomiting, diarrhoea, cramps, abdominal pain, cardiac, renal and pulmonary insufficiency.
Cicuta, Cat's parsley (Cicuta Virosa L.) — all parts of the plant are poisonous. Causes convulsions ending in death.
Clematis (Clématis) — causes diarrhoea and vomiting.
Colchicum (Colchicum) — all parts of the plant are poisonous.
Crocus or Saffron (Crócus) — causes diarrhoea and vomiting.
Cyclamen (Cyclamen) — its juice irritates the eyes and skin. Causes vomiting, diarrhoea, cramps, abdominal pain, heart, kidney and pulmonary insufficiency. Causes cardiovascular disorders.
Cyperus (Cyperus) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency, cardiovascular disorders.
Delphinium aka larkspur, Spurrier (Delphínium) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Dieffenbachia seguine (Dieffenbachia seguine) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Digitalis (Digitális) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency, systemic toxic effects, heart failure.
Dogwood (Córnus) — can cause swelling of the mouth.
Dracaena bordered (Dracaena marginata) — can cause swelling of the mouth.
Epipremnum (Scindapsus или Epipremnum) — if severe poisoning occurs, diarrhoea can begin.
Euphorbia or Euphorbiaceae (Euphorbiaceae) (all kinds), including Poinsettia aka Euphorbia Beautiful (Euphorbia pulcherrima) — cause contact dermatitis of the mouth or in the place of contact.
Ferns (Polypodióphyta) — causes diarrhoea and vomiting.
Ficus (Ficus) (different types) — cause burns, if ingested — kidney damage; contact dermatitis at the point of contact. Ficus (dwarf, Benjamin) — causes oral dermatitis. Ficus climbing — causes irritation (rash), if it was in contact with the skin.
Gardenia jasmine (Gardenia jasminoides) — may cause irritation (rash) if in contact with skin.
Geranium, aka pelargonium (Pelargonium) — causes indigestion.
Gloriosa (Gloriosa) — deadly poisonous.
Grape maiden three-pointed, aquifolium (Parthenocíssus tricuspidáta) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Havorthia (Haworthia) — can cause swelling of the mouth.
Heliotrope pubescent (Heliotropium lasiocarpum) — poisonous aerial parts and seeds.
Hellebore (Verátrum) — causes diarrhea, vomiting, even death.
Henbane (Hyoscýamus) — systemic toxic effects.
Hemlock (Cónium) — systemic toxic effects.
Hemp (Cánnabis) — hallucinogen.
Hogweed (Heracléum) — causes oral dermatitis.
Honeysuckle (Lonícera) — can cause swelling of the mouth.
Horse chestnut (Aésculus) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Hyacinth (Hyacinthus) — poisonous leaves, stems, flowers, bulbs.
Iris (Íris) — causes diarrhoea and vomiting.
Ivy (Неdera): platyagular, heart-shaped, ovoid, silver — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency. Boston ivy — causes oral swelling.
Jasmine (Jasmínum) or (Philadélphus) — systemic toxic effects.
Lakonos or Fitolacca (Laconos American — Phytolacca americana and Laconos berry — Phytolacca acinosa) — causes diarrhoea and vomiting.
Liliaceous (Liliáceae): autumn crocus (Cólchicum autumnále), hyacinth (Hyacínthus), lily (Lílium), etc. — contact can cause allergic dermatitis. White lily (Lilium candidum), "Red Princess" — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Lupine (Lupinus) — systemic toxic effects.
May lily of the valley (Convallária majális) — causes diarrhoea and vomiting.
Mistletoe, or oak berries, or bird glue (Víscum) — when ingested it contributes to disorders of the cardiovascular system and the central nervous system.
Monstera (Monstera deliciosa) — irritates eyes, skin.
Narcissus (Narcissus) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Oleander (Nerium oleander) — systemic toxic effects.
Palmcrist (Ricinus communis) — causes diarrhoea and vomiting.
Peperomia (Peperomia) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Periwinkle (Vínca) — hallucinogen.
Petunias (Petunia) — causes diarrhoea and vomiting.
Philodendron (Philodéndron) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure. Juice contains oxalic acid, can cause burns, kidney damage and central nervous system.
Physalis (Physalis) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Poinsettia or Euphorbia finest (Euphorbia pulcherrima) — causes oral dermatitis.
Poppy (Papáver) — hallucinogen.
Primrose (Primuláceae), including Primula (Prímula) — juice can cause burns and allergic dermatitis.
Rhododendron (Rhododendron) — causes cardiovascular disorders, diarrhoea and vomiting.
Rhubarb (Rhéum) — systemic toxic effects.
Ruta fragrant or Ruta odorous (Ruta graveolens) — causes oral dermatitis.
Sansevera (Sansevieria) — causes allergic dermatitis.
Schlumberger (Schlumbergera Lemaire aka Epiphyllum Pfeiffer, Zygocactus Schumann, Epiphyllanthus Berger) — can cause swelling of the mouth.
Shepherd's purse (Capsélla) — various toxic effects.
Snowdrops (Galanthus) — poisonous flowers infused with water.
Solanaceae (Solanaceae): pepper (Piper), Physalis (Physalis), green potato tubers, etc. — systemic toxic effects.
Syngonium (Syngonium podophyllum) — can cause swelling of the mouth.
Tobacco (Nicotiána) — causes swelling of the oral cavity, impaired motor coordination and acute heart failure.
Tulip (Tulipa) — poisonous bulbs, juice of stalks is also dangerous. Causes allergic dermatitis.
Violets or Saintpaulia violet (Saintpaulia) — causes diarrhoea and vomiting.
Weeping Fig or Ficus Benjamin (Ficus benjamina) — may cause irritation (rash) if in contact with skin.
Wild grapes (Tetrastigma = indoor grapes = girlish grapes (Tetrastigma Vitis) or (Parthenocissus qiimquefolia) or (Ampelopsis)) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Wisteria (Wistéria) — causes diarrhoea and vomiting.
White acacia (Robínia pseudoacácia) — causes vomiting, diarrhoea, convulsions, abdominal pain, heart, kidney and pulmonary insufficiency.
Wolf bast, it is a common daphaw, or a dandruff, or a dead wolf (Dáphne mezéreum) — systemic toxic effects.
Wormwood Tauride (Artemisia taurica Willd) — poisonous aboveground parts.
Yew berry, Mahogany (Táxus baccáta) — causes diarrhoea and vomiting.
Zamia (Zamia) — may cause irritation (rash) if in contact with skin.

From Pectoral maine-coon cattery web-site http://pectorals.com.ua/articles.php?n=plants-that-are-poisonous-to-cats&id=2