Plant Allergies & Thinning Tomato Plants

Question:

I'm curious as to when a Liquidambar starts to produce pollen? I'm trying to figure out if it could be the source of our daughter's severe spring allergies.

Answer:

  • Liquidambar trees bloom in March. It produces both male and female flowers as separate structures at about the same time the leaves emerge from dormancy.
  • Plant pollen moves around by insects and the wind. Wind pollination requires light pollen and lots of it that can travel great distances. This is troublesome because it is abundant, easily inhaled, and likely to cause allergic reactions. Flowers that depend on bees, wasps, butterflies, moths, and beetles for pollination tend to produce heavy, sticky grains that are somewhat airborne.
  • My gut feeling is that your Liquidambar is not the culprit.
    • Instead, there may be multiple sources based on the plants in your yard. Foundation plants, especially next to windows and entry and doorways, can be an immediate source of problems for those predisposed to pollen allergies. Birch, Oaks, Cedars, Walnuts, and Olives, while Junipers, Privets, Podocarpus, and even lilacs are problematical trees and shrubs.
  •  I suggest purchasing a copy of Tom Ogren's book Allergy-Free Gardening. It's available online or maybe at a local bookstore. Tom has developed a system of rating plants as to their allergy level. The Ogren Plant Allergy Scale (OPALS) assigns plants, including edibles, a rating from 1 to 10, with one being the best for allergies and ten being the worst.
    • You're now able to identify the problem plant(s). Of course, this assumes you know the plant names in your yard. If not, take samples or pictures to your favorite garden center and have the nursery professional help with the names.

Question:

I have two tomato plants growing in large pots. They're doing well, but I'm concerned because they are so busy. Should I strip some of the growth off or just let them continue? 

Answer:

  • Tomatoes need to be bushy with lots of leaves.
  • The foliage cover is a type of natural sunblock protecting the ripening tomatoes from sunburn. Sunburn is a tan/beige spot on the fruits' south and southwest side. But, you can have too much of a good thing, so I'd selectively thin out the inside of the plant or the secondary shoot(s) that forms where a leaf connects to a stem.
    • The center of the plant(s) becomes crowded and dense as the plant(s) mature, especially when using a tomato cage. Thinning lets in more light, increase air circulation throughout the plant, and helps keeps the inside foliage from turning brown.
    • Thinning is repeated as necessary. In addition, you should also be on the lookout for the Tomato Hornworm. They like to hide out in the center of the plant and munch on the leaves. When caught early, you can just pick them off, or spray with BT or Captain Jack Dead Bug Brew for more severe infestation.