Thorn apple

With its exotic looking leaves and spiky seed capsules, thorn apple often baffles gardeners when it pops up unexpectedly. It is a valued ornamental annual but produces many seeds, so you may choose to remove it or prevent it self-seeding. 

 

Quick facts

  • Thorn apple’s botanical name is Datura stramonium  
  • Other common names include Jamestown weed, jimson weed, devil’s apple, devil’s trumpet and devil’s snare 
  • All parts of the plant are poisonous – wear gloves when handling and wash your hands 
  • If you need to control thorn apple, non-chemical methods are easy and effective 

What does thorn apple look like?

Thorn apple is fast growing, with the potential to reach a height of 1.5m (5ft) during a long, hot summer. Its exotic looking leaves have wavy, pointed edges. Wide, funnel-shaped flowers are produced from July to October. These are usually white but can have purple or lilac tints. The seed capsules are large and spiky, hence the common name thorn apple. These are toxic and shouldn’t be eaten.

Did you know?

Thorn apple seeds can inadvertently be introduced into gardens as a contaminant in birdseed mixes. It is often first seen growing on bare ground near bird feeders.

Is thorn apple a weed?

Thorn apple can be an attractive addition to gardens, particularly in tropical style plantings. Some seed companies sell it, emphasising its value as an ornamental annual plant. At night, the flowers open fully and release a pleasant scent, attracting moths.  

Despite its ornamental qualities, all parts of the plant are poisonous and handling it can irritate skin. Each spiky seed capsule contains many long-lived seeds. Seedlings usually appear in spring or summer and their fast growth competes with other plants for moisture, nutrients, space and light, so even if you are happy to allow some to grow, it is wise to limit self-seeding.

What is a weed?

The term ‘weed’ describes a plant that is growing where it isn’t wanted. Weeds usually thrive in average garden conditions, reproducing and spreading easily. It is up to you to decide what you call a weed and what you choose to retain or remove.

Frequently asked questions about controlling thorn apple

Here are our answers to your most common questions about dealing with thorn apple:  

How invasive is thorn apple?  

Thorn apple spreads by seed and these can remain viable (alive) in the soil for many years. However, plants often first appear in gardens individually or in small numbers, so are easily removed before they produce seed.  

Do I need to get rid of thorn apple?  

No – you don’t need to eradicate thorn apple from your garden if it has arrived unexpectedly and you want to enjoy its exotic-looking leaves and scented flowers. However, you may want to prevent it self-seeding. Young plants are fast growing and can easily compete with seedlings and small plants.

As it is a poisonous plant, you may wish to get rid of thorn apple if there is any risk that children or pets may eat or handle some. 

What is the easiest way to kill thorn apple?  

If you have thorn apple growing where it is not wanted, there are a few easy ways to remove it:    

  • Hoe off plants – sever the roots of young plants on a warm, dry or windy day, so exposed roots dry out quickly. Hoeing removes weeds with minimal soil disturbance.   
  • Pull or fork out plants – remove small plants by hand and lift larger ones with a hand or border fork. If you allow plants to flower, be sure to pull them out before they develop spiky seed capsules, to prevent self-seeding. Wear gloves when handling thorn apple.   
  • Smother plants – prevent seeds from germinating by covering the soil in late winter with a mulch of organic matter about 8cm (3in) deep. Alternatively, fill gaps in borders with ground cover plants to out-compete thorn apple seedlings.
Top Tip

Your home compost heap is unlikely to get hot enough to kill thorn apple seeds, so if plants have already set seed, add them to your green waste collection bin or take them to your local garden waste site. For more advice see our handy guide on dealing with garden waste

Should I use weedkiller? 

As thorn apple is easy to control by hoeing and pulling out, there's no need to use a weedkiller.

For more information, see our page on Weeds: non-chemical controls.

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