20 January 2021

Applying Nemaslug and soil temperatures

Q. “I wonder if you can clarify somethings about the temperature this works at. On the website it says that it needs a temperature of 5 degrees C. I presume this means that it needs a temperature above 5 degrees C? But I’m confused – it also says to keep it in the fridge – which I think is less than 5 degrees C, so I’m a bit confused! I suppose in short, I’m wondering, if I put it straight on the garden, which is currently somewhere between 0 degrees and a balmy 8 degrees, ie. somewhere in the refrigeration range, will it kill them or will they sit there happily as though they were in a fridge, until warmer weather during the days (but then back to 1degree or so at night). I just don’t really know what temperatures I’m looking for when it says 5 degrees. ?persistently above? or doesn’t matter? Should I go for it now? The slugs are already happily munching away on my delphiniums” Thanks Dawn by email

A. Thanks for a great question. The nematodes are active at temperatures of 5c and above, so we refrigerate them to keep them in tip top condition and then once you apply them to the soil they become active. As you suggest, if you apply them early in the season when night time temperatures drop, they will be active during the day and then become sluggish (pardon the pun) during the night when temperatures drop and then become active again once daytime temperatures rise again the following day. The only word of caution is that if we were to have a hard frost after you have applied the nematode then this can kill them. I normally let the slugs be the guide i.e. if the slugs are active and you say your are then it is normally warm enough in the day, so I would go for it unless a really hard frost it forecast. I hope this helps. Jon @ Green Gardener. CLICK HERE to find out more about Nemaslug Slug Killer.