Plants in NZ That Are Harmful to Horses and Safe Alternatives
In New Zealand, a number of common shelter trees, garden ornamentals, weeds, and hedge plants can pose serious risks to horses — even in small amounts.
Knowing which plants are dangerous, and which are horse-safe, is an important part of managing paddocks, lifestyle blocks, and equestrian properties.
Common Toxic Plants for Horses in New Zealand
Ragwort
Ragwort is one of the best-known poisonous weeds affecting horses in New Zealand. It contains pyrrolizidine alkaloids that cause irreversible liver damage over time.
Symptoms
- Weight loss
- Depression
- Poor coordination
- Photo sensitivity
- Liver failure
Risk Level - Very high — especially in hay.
Oleander
All parts of oleander are extremely toxic to horses. Even small amounts can affect the heart and may be fatal.
Symptoms
- Colic
- Irregular heartbeat
- Sweating
- Sudden death
Never place oleander garden trimmings where horses can access them.
Yew Trees
Yew is highly poisonous, and horses can die very quickly after ingestion. The leaves and seeds are the most dangerous parts.
Symptoms
- Sudden collapse
- Breathing difficulty
- Often little warning before death
Because of the risk, yew should never be planted near paddocks.
Rhododendron and Azalea
These popular ornamental shrubs contain toxins that affect the nervous and digestive systems.
Symptoms
- Drooling
- Weakness
- Colic
- Heart problems
Even a relatively small amount can cause poisoning
Macrocarpa and Pine Needle Issues
While not always directly toxic in small amounts, large quantities of fallen needles or shelter tree debris can contribute to digestive upset and abortions in pregnant mares. Care should be taken with shelter belts around horse paddocks.
Acorns and Oak Trees
Oak leaves and acorns contain tannins that can damage the kidneys and digestive tract when eaten in quantity.
Symptoms
- Colic
- Constipation or diarrhoea
- Kidney damage
- Lethargy
Autumn is the highest-risk period.
Garden Plants to Keep Away fromHorses
Many attractive garden plants are unsafe around horses, including but not limited to:
- Foxglove
- Lily of the valley
- Hydrangea
- Daphne
- Nightshade
- Laburnum
- Ivy
- Privet
Horse-Safe Trees and Plants for New Zealand Properties
The good news is there are many attractive and practical plants that are generally considered safe for horses.
Kanuka and Manuka
These hardy natives pecies make excellent shelter and are commonly used in revegetation planting.
Benefits include:
- Hardy in NZ conditions
- Good shelter
- Pollinator-friendly
- Generally horse-safe
Pittosporum
Many pittosporum varieties are used successfully around equestrian properties as shelter and hedging.
Popular choices include:
- Pittosporum tenuifolium
- Pittosporum eugenioides
- Compact hedge forms
Griselinia
Griselinia is adurable shelter and screening plant widely used on lifestyle blocks.
It offers:
- Fast growth
- Wind tolerance
- Dense shelter
- Low maintenance
Flax (Harakeke)
New Zealand flax is widely planted around wetlands and paddock margins and is generally regarded as safe around horses.
Healthy pasture reduces the likelihood of horses browsing toxic plants.
Tips for Keeping Horses Safe Around Plants
Regularly InspectPaddocks
Walk paddocks frequently to identify emerging weeds or fallen branches.
Check Hay Supplies
Toxic weeds can remain dangerous even after drying.
Fence Off Risk Areas
Prevent access to gardens, shelterbelts, and compost piles.
Never Feed GardenClippings
Many poisonings occur from dumped trimmings.
Introduce Horses Gradually
New horses may sample unfamiliar plants out of curiosity.
If in doubt call your Vet. Early treatment can make a major difference.
