So with the rainy season about to begin it might be time to order up some predatory nematodes if you suffer from cutworms (ネキリムシ) or other soil dwelling pests in your growing area. They come in two sizes for either small veggy patches or large field application, here is the larger size
They aren't cheap, that pack costs 13,000円. As an example, last year production was suspended so we couldn't buy them and we lost nearly our entire carrot crop which amounted to 8,000円 in seeds, lost time seeding and then weeding the carrot beds and lost sales plus losses to other crops where the cutworms destroyed young plants. All in all a lot more than the price of a pack of nematodes.
Packs for home garden plots can be ordered
Here
Larger packs can be ordered through your local seed shop, product information is
Here or online.
They will store in the fridge for around 3 months. Ideal application time is in the evening just before a few days of rain, so right in the middle of the rainy season is perfect. for small areas a watering can is ideal for larger areas then a lorry tank and pump will work well, ideally a low pressure pump rather than high pressure spraying pump. I use a Koshin Hidels Pump with ordinary hose and shower head as it's far gentler than our higher pressure spraying pump.
Not all crops need protecting and ideally make two applications spread over about a month to get the best coverage.