10 plants with irritant sap

Aconitum

Aconitum napellus is also known as monkshood, wolfsbane and aconite. It contains a powerful toxin, aconitine, which can kill people who come into contact with it. All parts of the plant are toxic but the sap in particular is a skin irritant, causing burning of the lips and mouth, vomiting, diarrhoea and spasms.

Alstroemeria

Every part of alstroemeria can be toxic, thanks to the compound tulipalin, which is produced when plant tissues are damaged such as when pruning or deadheading. Ingesting the sap can cause mild vomiting or diarrhoea, while skin contact can cause a rash or irritation and, rarely, blisters and eye irritation.

Echium

Sap from all echiums, including viper's bugloss, Echium vulgare, can cause skin irritation such as a burning sensation and possible blistering, and be mildly toxic if ingested.

Capsicum annuum

While the fruits of Capsicum annuum, which we know better as chillies and sweet peppers, are completely edible, the sap can irritate the skin and potentially cause it to blister.

Euphorbia

Euphorbias have a particularly milky sap, which is extremely irritating to the skin and eyes. The sap can cause burning to the skin and if it comes into contact with your eyes then you may experience a burning sensation, swelling and temporary loss of vision for up to two weeks. As well as wearing gloves when handling euphorbias, gardeners should also wear eye protection.

Chrysanthemum

Chrysanthemum sap contains the phytochemical compound Alantolactone, which can irritate skin on contact and increase sensitivity to sunlight.

Weeping fig

Weeping fig, Ficus benjamina, is a popular houseplant. However, contact with its sap can cause an allergic reaction including dermatitis and increased sensitivity to sunlight, especially for those who are allergic to latex. In rare and extreme cases, contact with, or even exposure to, ficus sap, can result in anaphylactic shock.

Parsnip

Parsnips, like all members of the carrot family have irritant sap that's absorbed by the skin and, when combined with sunshine, can cause extreme sunburn, itching and blistering.

Philodendron

Another popular house plant, philodendron can cause mild irritation on contact with the sap. The sap is also poisonous when ingested, but only in large doses.

Nerium oleander

Plants with irritant sap - Nerium oleander

Oleander contains many toxins, which are found in all parts of the plant. Ingestion of any part of the plant can cause serious illness and, in extreme cases, death. Contact with the sap can cause skin rashes and burns, and blurred vision.

Other plants with irritant sap:

• Anthurium
• Arisaema
• Arum
• Calla palustris
• Daphne mezereum
• Hyacinthus
• Iris
• Lobelia
• Narcissus