If (when) the ambient air temperature surpasses 80dF, the plants will stop growing and likely wilt (particularly if not watered daily). If this occurs, keep watering; maintain hope, they should regrow once the temperatures drop again. Do not compost the plants; they are only waiting for the temperatures to drop again. Remember, wasabi is really hardy. See our blog post about plants being in the refrigerator for 8 months in a totally sealed/anaerobic environment and still growing. If you garden is too hot, keep watering, or if you planted them in a sunny location, use this opportunity to transplant them. The plants in the shrubbery below are under the blackberry hedgerow. They've been there for 5 years. We've been monitoring them. We tossed offshoots here as an experiment. No watering, no tending, no special sauce, no care whatsoever (and no sunlight in the summer months). The plants are growing each year. They reduce a bit in summer and rejuvenate in Autumn and really reinvigorate in the Spring. If these are any example for you; keep watering. Wasabi's natural habitat is alpine streams; under fir canopy and in or near streams with that cold water and air cell around it. (Ever walk near a stream on a hot summer night when the air was still and the temperature drops ~15d?) Once the plants are outside their desired conditions, they rebel by shutting down to preserve energy. Just don't let them get dry and they should rally once the scarves return to your wardrobe.