|‘Micro Spider’ or Mealybug?||| Print ||
|Thursday, 03 January 2013 12:31|
By Buzz Bertolero
The Dirt Gardener
Q: Since July, the leaves of my silver-veined fittonia have developed patches of white, fuzzy stuff along with being sticky. It sits on my office desk and now my co-workers have noticed that it looks sick. You can imagine my embarrassment! I’ve been rubbing the white puffs away when I see them, but it keeps returning. I’m wondering if it may be a “micro spider” and what I can do to stop this?
A: A workplace is stressful enough without having your plants embarrassing you. I’d take the fittonia home for recovery and replace it at the office with one that is lush and thriving. The overnight revival will make great water cooler conversation.
The white stuff on houseplants is usually one of two things: powdery mildew or mealybug and not a “micro spider.”
Powdery mildew is a fungus disease that covers the leaf surface with a white film. It can cover the entire leaf or be in random spots. In severe cases, it will also coat the leaf petiole and stems.
I do not believe this is your problem, as powdery mildew is not sticky to the touch, while mealybug can be.
Mealybug is a sucking insect like an aphid. It produces white stringy filaments to cover itself. At a glance, it looks more like a cotton ball.
Mealybugs feed on the plant’s juices. These juices are secreted as a clear, sticky substance called honey dew. It’s a problem on indoor herbaceous plants, palms and other tropical plants.
With a persistent problem, I’d control the mealybug with a granular systemic insecticide instead of the typical insect spray.
Systemic granules are applied to the soil and available at most garden centers. The insecticide is then transported throughout the plant, controlling the mealybug when they attack.
Q: Many years ago, we planted a climbing rose on the south side of the house. It’s been somewhat neglected; so it is two stories high, very woody and doesn’t bloom on the lower half. Can I prune it severely to bush it out; and, when is the best time to do so?
A: Sure you can prune climbing roses severely just like a bush rose. The primary season to prune it would be now through the end of February.
Before pruning a climbing rose, you should try to determine whether it is a hybrid tea, grandiflora or floribunda type rose. The flowers bloom on the second-year wood of hybrid teas and grandiflora, so heavy pruning will prevent it from blooming next year.
Floribunda-type climbers bloom on the first-year wood, so heavy pruning shouldn’t affect it as much.
Hybrid teas and grandiflora-type roses have the large flowers while the floribunda flowers are much smaller, about the size of a 50-cent piece. If you’re not sure, then I’d consider not pruning and instead plant another climber at the base to fill in the blank area.
Newer varieties are advantageous as they bloom on both the old and new wood, so you don’t have to be careful pruning them.