Using Nematodes

You'll be fine to apply both 'Nemaslug Slug Killer' and 'Nemasys Grow Your Own' onto the same plot.

From my knowledge 'Nemaslug Slug Killer' contains a single species of nematode which is absent from 'Nemasys Grow Your Own' however there are varying levels of these occurring naturally in the soil and so undoubtedly coming into contact with one another, but being host specific neither should attack the other.

So providing they are applied in the correct manner (and preferably under the best conditions) they should all do their job fine.