Working with Toxic Plants - Bali Advertiser (2024)

A few days ago I was clipping in my garden and some sap from a shrub got on my hand. I just brushed it off but later it caused irritation that lasted for over a week. Are there certain types of plants that we should be careful of?

Many people can become sick through exposure to toxic plants, but in most cases it is an allergic skin reaction that could last a number of days, though in some cases people can suffer prolonged periods of dermatitis even for years after the initial contact. It is helpful if you can identify toxic plants or plants that are likely to cause allergic reactions growing in the garden, so that you can better manage them and provide a safer environment for all of those who come into your garden. When it comes to garden maintenance, all plants with milky sap have to be treated with care and caution. Some examples of this are plants that are very common in the home garden. Frangipani, euphorbia and oleander are the immediate examples that spring to mind. Frangipani is related to the oleander and both possess a poisonous, milky sap, which is similar to that of euphorbia. When trimming all of these plants one must be very careful not to let any of the sap come into contact with the eyes or skin.

Euphorbia all have the milky sap that can cause allergy to the skin and it is extremely irritating if on the lips or in the eyes. It is also quite toxic if one should actually eat enough of it. I seem to have a low sensitivity to euphorbia sap, but I have a friend who is highly sensitive and breaks out in a severe rash whenever he touches it. I have gotten some euphorbia sap in my own eyes after getting sap on my hands, forgetting, and then rubbing sweat from my brow. It was a very unpleasant experience to say the least, though I have never experienced the sap from a frangipani in the eye though I have heard plenty of stories. It can hurt for days and people can go temporarily blind. Many people do not know that the milky sap that comes out of a frangipani is toxic to humans and animals. If you propagate from cutting then you should always wear protective eye wear and make sure children or pets are not within the vicinity. There have been many occurrences of temporary blindness caused by frangipani sap.

Contact with the milky sap may also cause skin irritation, burning, itching, rash and allergy, that in some people can last for weeks, even years developing into conditions such as eczema and dermatitis! Simply break a leaf and the frangipani starts dripping with sap. It is more of an irritant than a serious threat to life (unless a significant amount is ingested). Frangipani sap in the eye is very possible as you often have to prune these trees overhead and the sap which comes from the branches constantly drips. It is a good idea to avoid anything in your eyes from the garden. I recommend using goggles if there is likely to be a situation where plant material can get into your eyes the same applies to tree ferns which also have a nasty sap.

The oleander, in a league of its own, is one of the most deadly plants, and now widely cultivated throughout the world. It is also tremendously popular as a decorative shrub. This is a plant that you should familiarize yourself with. The plant contains numerous toxins, and all parts are very toxic. Oleander is deadly if ingested, and contact with the leaf alone can cause severe skin irritation. Just one leaf can kill an adult, and fatal poisonings have resulted from minimal exposure to the sap, twigs, flowers and berries. Fatalities among horses and livestock are common. I would remove this plant from any garden where children are likely to regularly play. Burning this plant can also create a deadly toxic smoke, so don’t do that! Small children should always be supervised when in the presence of an oleander tree. In addition to milky sap, foliage plants that you need to be careful of around children include philodendron, croton, alocasia, draecena and caladium. There are oxalates in the leaves rendering most of these plants toxic. Ingesting oxalates causes irritation all along the digestive tract and is usually regurgitated.

Mangoes are a common fruit that is very well known for causing allergy, a type of contact dermatitis which occurs when the sappy substance comes in contact with the skin. Urushiol, is the allergen and is present in the skin of the mango, it turns black in contact with the air, and can be easily seen as the black sticky deposit on the mango fruit. It is important to note that the sap can be picked up through secondary contact such as residue on a knife handle. I have witnessed numerous cases of mango itch. A friend once had a particularly severe reaction, fever with large red welts all over his skin, and bed ridden for days. Luckily, mango flesh has very low levels of Urushiol, so most sensitive people can eat the fruit as long as someone else peels the mango.

Two of the most common vegetables grown in the garden are the potato and the tomato. The leafy parts of both plants are highly poisonous. Green tomatoes are toxic unless they are cooked, and potatoes are very toxic as soon as they turn green, so if this is the case throw them out. Another little known fact is that apple seeds are poisonous, containing small amounts of cyanide. The quantity contained is usually not enough to be dangerous to humans, but it is possible to ingest enough seeds to produce a fatal dose. So when you make fresh apple juice always remember to remove the seeds.

It is not always easy to know which plants have toxic sap and which don’t. Personally, I would avoid any plant saps on my skin eyes or mouth. Toxic and irritating saps are certainly not unique. Some agaves have toxic saps, as well as many fig species. Generally if a plant causes skin irritation it is most likely toxic if ingested. If the sap gets in your eyes, it can temporally blind a human or animal. Animals and small children can be especially affected if they consume the sap, it could make them sick or even possibly kill them. On the bright side all of the waste from poisonous plants can be composted as the toxins are biodegradable, but never burn them as you would be creating a toxic smoke that could be very dangerous or even lethal. Plants that are toxic to adults will have a much greater toxicity to animals and children. Always assume that kids and pets will explore and experiment with garden plants, and thus manage your garden environment accordingly. The aim is to enjoy the garden, not to get sick from it!

Wear a hat, gloves, long sleeve shirt, and long trousers when pruning these plants. If pruning overhead wear protective eye wear. Be careful in hot weather, if you start to sweat, never use your gloves to wipe your brow. If you get sap in your eyes, you’re off to the hospital. Do some further research on your own garden, because plants with toxic properties are many more than I can reasonably cover here.