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  • Writer's pictureSimone Boyd

Treated seeds - what's the big deal?

I recently made a rookie error! I failed to complete a seed inventory last Summer, and inadvertently used most of my white icicle radish seed, which is one of my favourite Summer radishes. I went to sow a bed before the rain we recently received, and realised I would not have enough seed to see me through this coming Summer. Silly me!

Never mind though - introducing new genetics to my seed supply is never a bad thing, so I began trawling through my preferred seed supplier websites searching for a bulk amount of white icicle radish seeds, from which I could select the best crops to save seeds from at the end of the season. Now, the important thing to note here is that as an organic grower, I have no interest in treated seed – that is, seed which has been treated with fungicides, pesticides or any other chemical treatment including genetic modification (the latter of course renders them "definitely not an heirloom" variety). Usually, these seeds are not too difficult to find, however this season I struggled to find any untreated radish seed through my usual suppliers. So I looked further afield and after some time, I found a supplier which clearly listed their white icicle radish seeds as untreated, and could offer a bulk quantity. Excellent! I prefer to trail a small batch before I buy a bulk quantity, so only ordered 10 grams of seed, intending to buy more if they proved to have good germination, and great taste.

You can imagine my frustration when the packet arrived, with the label attached (as pictured above). "CAUTION: Treated with Thiram…" I contacted the seed company expressing my concern and received no response during the next 48 hours. What I did notice however, was that upon receipt of my email, they immediately updated their website to state the seed being supplied was treated. Great for the next purchaser, not so great for me. I decided to undertake a little research into Thiram – to see just how bad it could be. Well…

According to the Safety Data Sheet or SDS released by accessed 19/10/2023; 1500hrs)

This product is classified as: Xn, Harmful. Xi, Irritating. N, Dangerous to the environment.

H302: Harmful if swallowed.

H315: Causes skin irritation.

H317: May cause an allergic skin reaction.

H319: Causes serious eye irritation.

H332: Harmful if inhaled.

H341: Suspected of causing genetic defects.

H373: May cause damage to organs through prolonged or repeated exposure.

H410: Very toxic to aquatic life with long lasting effects.

The SDS is eight pages long, and I will allow you to access the SDS yourself if you are interested in the whole picture. Needless to say, the seed will not be planted within my market garden and has been disposed of.

I will ensure the healthiest white icicle radish crops from this season are kept to supply me (and possibly you) with chemical free seed next season.

In the meantime, I am happy to guarantee that seeds purchased from us at Heirloom Naturally are not treated with chemicals, you do not need to wear gloves when sowing, or avoid inhaling any dust when sowing etc, etc, etc. If you are doing your very best to grow without chemicals, ensure you are aware of where your seeds are being grown, what if anything they have been treated with and what impact that treatment might have on you, your soil or surrounding environment's health.

The seed we make available to you is grown and processed within our market garden in Mansfield Victoria, and shipped to you within 48 hours of receipt of your order. And – I guarantee to respond to any email queries in a prompt and courteous manner.

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