Q: I purchased a “My Monet” weigela a number of years in the past. It seems wholesome and is rising properly. I purchased it for the variegated leaves, however for the previous couple of years, the brand new development is simply plain inexperienced. What occurred and can the leaves ultimately flip white and pink like they’re presupposed to be?
A: Variegation is definitely fairly cool. It’s brought on by genetic modifications in plant cells. This may occur naturally from a spontaneous mutation or a viral an infection. It can be pressured by plant breeders utilizing chemical substances or irradiation. The affected space is unable to supply chlorophyll, the stuff that makes a leaf inexperienced, in order that space is white or yellow. The variegation might be over the entire plant or, within the case of a virus, simply on a part of a leaf or flower. A few of these modifications are everlasting. Others are much less secure, and new development needs to revert again to its all-green state. This reversion is extra doubtless when a plant is burdened by extremes in temperatures or when it wants extra mild than it’s receiving.
White or variegated leaves are usually not as strong as inexperienced ones. They want extra mild to compensate for the shortage of chlorophyll, which is required for photosynthesis, the turning of sunshine into vitality.
Your all-green leaves is not going to flip variegated. Reduce out the inexperienced branches to their bases in order that they don’t overpower the weaker variegated branches. It’s your decision see should you can improve the sunshine the weigela is getting, both by trimming close by crops or transferring it. If a variegated plant isn’t getting sufficient mild to photosynthesize, it can preserve producing inexperienced leaves or will falter.
Genetically, when one thing has two completely different cell patterns in an element the place it usually would have one, like in a multi-colored leaf or flower, it’s referred to as a chimera. Plant breeders take elements of chimeral tissue which have a fascinating high quality, akin to an attention-grabbing shade or higher fruit, and propagate it to supply among the crops and the produce that we purchase. If you wish to learn an in-depth article on chimeras, see aggie-horticulture.tamu.edu/tisscult/Chimeras/chimeralec/chimeras.html.
Written by U of M Extension Grasp Gardeners in St. Louis County. Ship inquiries to firstname.lastname@example.org.