How should you dispose of Himalayan balsam seeds?

As a result of clearing Himalayan balsam and catching the pods that were about to pop, I now have three carrier bags of seeds and associated pods and flowers. They are too wet to burn. You aren’t allowed to put them in the green waste recycling bin. Has anyone got suggestions of how to dispose of them, please? I’m thinking maybe an oil drum, but how long would I need to store it for to be sure the seeds were dead?

I would chop it all down and bake it in the sun until it is dry preferably before it flowers. There is then a choice to burn it if there is seed or compost it if it has not started to flower.
It is probably easiest to germinate the seed and kill the seedlings before they flower.

Can’t they just be composted? If the seeds germinate at all, the darkness of the bin/composter would prevent growth, especially if regularly turned.

The seeds are all in one big batch.
The quickest solution is to germinate them and kill the seedlings.

Thanks for the responses. The county council runs a composting scheme but they emphatically don’t take balsam (or any other invasives or poisonous plants. I wonder how they decide what is poisonous), so if they don’t have faith in their composting process, I wouldn’t rely on a diy compost bin to kill them.

Germinating them and killing the seedlings sounds OK, but how would you manage it? In big plant pots? On damp tissue like mustard & cress? They probably won’t germinate until spring, and then when you have had a flush of seedlings, how do you know if there are still dormant seeds among them?

Any thoughts on the effect of putting them in a freezer? I’m not sure if that would kill them or just suspend their aging process and keep them viable longer.

I’m also wondering about tipping them in an area that is already infested with balsam. There there is annually intense competition between the seedlings and they thin themselves out, so more seeds couldn’t make the situation worse.

Just put the seeds and shells in a solid tray without drainage holes on a very thin layer of soil in a warm indoor place and water them and after they germinate. They will use up the water. Allow them to wither and die. Repeat the watering and drying several times until there is no more germination.

This document should answer your questions. Jones D (2022) Public information on invasive species in Wales: Himalayan balsam. Welsh Government:

Thanks. Yes, I’ve seen that. It mentions the need to take seed pods off before you pull a ripe plant, but doesn’t suggest what to do with them afterwards. Though it does recommend leaving pulled plants in a pile onsite, which make me think that might be where to put the pulled seeds also.

very informative thread thanks John and others. It is very rare in my County

The Welsh paper doesn’t specifically state what should be done with the seeds other than dispose of then following ‘good biosecurity procedures’. It does go on to say that all plant material including soil contaminated with seeds is a ‘controlled waste…’. My interpretation of this would be moving the seeds to another infected site contradicts the guidance.

Page 7: Treatments 2 & 3: Notes

“Himalayan balsam should not be allowed to flower or set seed. However, in certain limited circumstances, flowers and seed pods can be carefully bagged by dipping the top of the plant into a large transparent bag (so you can see what you are doing!) and pulling it off – minimise this procedure as it takes a lot of time and some seeds will inevitably escape. Dispose of flowers and seed pods along with other waste away from water following good biosecurity procedures as sticky seeds will adhere to boots and clothing.“ and,

‘Himalayan balsam plant material (including soil contaminated with seeds) is a ‘controlled waste’ under the Environmental Protection Act 1990 which means it can only be transported by a registered waste carrier to suitably permitted or exempt sites; do not move any plant or soil waste generated by management from the area where it produced.’

It depends what the definition of a site is. If you take the seeds from an area you have cleared of balsam and put them on a patch of the same farm that is still infested with balsam, have you moved them to a different site? But the problem there is the voles will take them away and bury them, so the seeds still get dispersed.

I”m currently looking for an oil drum or equivalent to drop them in and forget about them for a few years.

Hi John
Yer right - dump it in an infested place, in as compact a heap as possible and above any flood zone (the seeds wash downstream and spread the problem). A dry dark spot is best.

Stick them in a microwave oven for a while … though to stay within the letter of the law, you may have to take the microwave to the seeds rather than vice versa :wink:

Thanks for the suggestion. There are about three gallons now, so quite a load to take home on the bus and to microwave. It isn’t just dry seeds. When you grab them to stop them exploding over the ground, you get petals and some stem too, so it is quite a wet mixture, and quickly goes smelly as I found yesterday when the bag dripped over my rucksack.

You are doing a good job of seed dispersal :slightly_smiling_face:

Why do you say that?

Just the act of getting close enough to grab the plants when they are in seed will have caused an eruption of seed dispersal even before being bagged.
Surely it is logical to gather the plants when they are half grown before they flower and no way when they have pods.
I know your motives are good, but surely this late in their season, you are fighting a losing battle.

This is one of those occasions when I have to pause and resist the temptation to fire off the first response that comes into my head.

I would assume that bagging them, however inefficient, disperses fewer seeds than not bagging them.