Hello Orchid Growers March 2021
We hope all are safe and well. Covid virus situation continues to cause disruption and restrictions. We managed the need to escape for a period of social isolation – camping and fishing.
In this Newsletter shown are some more recent flowerings in our collection. I am probably a better camper than orchid grower (and fishing is pretty hit and miss!). Shown are some of my camp meal creations all cooked with only a camp oven, frypan, pair of tongs and flipper. I am no Master Chef but often think that everything in our lives seems so complicated but can be so simple.
We have been seeing many growers expressing problems with mealybugs this season, so following is some information which may be of assistance.
Mealybugs and Orchid Growing
What are Mealybugs?
Mealybugs are a small insect very closely related to scale. Both can be very damaging to orchids if left to run riot. Normally they are recognized as “Fluffy” white or pale coloured clusters on leaves or pseudobulbs. If very serious infestation they will also be found in the roots, rhizomes and potting mix.
They are a sucking insect and cause considerable damage by their feeding weakening the orchid and flower vigour. They also cause tissue damage in feeding that may allow fungal and bacterial problems.
How do I get Mealybugs?
- By your plant acquisition. This is the most common way orchid growers introduce it to their collection. I have seen some terrible examples of this in various social media platforms and large retail outlets recently. It comes free with your “bargain’ purchase!
When you introduce new orchids to your collection you should examine them closely for any signs of infestation and isolate them for a number of weeks.
- You have a breeding ground in close proximity to your orchid collection. Some types of plants are a haven for Mealybugs. Most palms will have considerable infestations observed when you peel back the base of the fronds. Many weeds are also a major source.
I ended up removing all the palms that were directly adjacent in the gardens surrounding my growing areas. I also keep weeds to a minimum in the growing areas. Mealybugs can in a limited way move around by their own means, but travel greater distance by wind movement or hitchhiking on ants. The source of my potential problem was removed.
What control measure can I use?
- “Home” recipes. There are many of these espoused in various forums but are most generally not effective with serious infestation.
- Rubbing Alcohol. Swabbing the infestation areas with cotton dipped in 70% isopropyl alcohol is effective for small infestation. You can also use a fine spray mix. It is useful for leaf and pseudobulb infestation but not so good for root infestation.
- Pest Oils and Soaps. Various Pest Oils and Soaps are effective and work by smothering the Mealybug. It is necessary to spray 3 times at 10 – 14 day intervals in line with the further breeding cycle of the Mealybug. When spraying with Pest Oil it is very important not to spray when temperature is over 30 degrees and increasing as damage to flowers and foliage will occur. These methods are effective for foliage infestation but not so good for root infestation.
- There are various insecticides approved for ornamental plant treatment for Mealybug. If infestation is very serious then this is probably your only chance of control of both foliage and root infestation. Again, spraying is necessary for at least 3 times at 10 – 14 day intervals. Unfortunately, many strains of Mealybug become pesticide resistant so it is necessary to use a couple of different sprays.
- Repotting and Washing. For very serious infestations this is very effective but time consuming and costly. The plants need all the old roots and compost removed and pots sterilized. Foliage and rhizomes can be scrubbed with one of the previous control measures and the entire plant washed and soaked in soapy water.
Thank you for support
Ross and Liz