Jerry Brust, IPM Vegetable Specialist, University of Maryland; jbrust@umd.edu
This is a quick note to say that after looking at some strawberry fields in which the transplant plugs were wilting it at first looked like there could be some root disease problem. But under our very dry conditions (except for the nice rains this past Wednesday, 16th) for the last 6-8 weeks this did not seem probable. In several fields nearly 100% of the transplants were wilting with the older leaves brown, shriveled and dying and the younger leaves still green but flaccid (Fig. 1). Looking at the root ball showed that the plugs were very dry (Fig. 2), even though the grower had been irrigating. Once root plugs dry out they are very difficult to re-wet without water being applied over time directly to the root ball. In some situations the soil around the root ball was moist, but the plug was still dry. Even though some plugs had been in the ground for weeks there often was little root growth outside of the root plug (Fig. 2). I think this is what happened in many fields over the last few weeks, the root ball dried out and the moisture from drip tubes that were often 3-8 inches away from the transplants was not enough to re-wet the dried out plugs. Besides being dry we also had bright sunny days with low humidity making for a very dry environment. While dry strawberry plugs may explain some of the wilting that is going on with new strawberry plugs, it is a good idea to check wilted plants in each case to see if it is dry plugs or something else. I think with the rain we had this past Wednesday most of the dried out plugs should be re-wetted and will be good to go.
Figure 1. Wilting strawberry plant
Figure 2. Strawberry plug that is very dry