Impacts of late winter weather and tips from a Horticulturist

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Insights from horticulturist during this Illinois late winter/early spring:

  • Do not remove debris or mulch too soon as part of spring cleanup. It is a common practice to mulch in the winter to prevent frost heaving of perennials. When the plants are heaved the plant crowns are then exposed to cold weather. If the temperatures were to drop too low, this would be an issue with whether the plant survives our winter or not.
  • Warmer temperatures may shorten the flowering time of bulbs. Cooler springs extend the lives of our favorite bulbs but if it remains too warm, they will not last long. If it frosts after they have sent up a bud, they may not flower at all. However, the bulb health would not be affected by early flowering and will rebloom the following spring.
  • Warmer temperatures allow more spores and structures of diseases to survive in debris and litter. Warmer temperatures are more suitable for pathogen growth and reproductions and may cause an expansion of the disease range. The epidemics may be more severe and occur earlier than usual. Be on the lookout for disease if we remain wet and warm.
  • Cold temperatures help maintain normal plant cycles. According to horticulture educator Chris Enroth, "If your apple tree in the backyard requires 1,000 chilling hours, it is a safe bet these warm temperatures are not going to be enough to trigger growth. However, if your peach tree (a notably more southern crop) has a chilling requirement of 400 hours, you may want to invest in some winter protection for the possible emergence of flowers."
  • The upside to warm winters is the root zones remained warmer. Warmer root zones have been linked to heavier flower production, but they may be more sporadic.
  • As for bugs, horticulture educator Richard Hentschel said that "because cold temperatures arrived late, more bugs had the chance to find a spot to hibernate for the winter, and that often was around people's houses. The warmer temperatures caused bugs to come out of dormancy and search for warm spots, which happen to be inside people's homes."