unknown pests
by anja
(mn)
I have a clay planter with two pest problems in the planter; I have an Aeonium species known as 'Irish Bouquet', a Crassula argentea or finger jade, an Echeveria 'Lola', a torch cactus and a split rock living rock, Pleiospilos nelli. In the soil there are some silvery dark grayish bugs which seem to stay in the soil under rocks and around the base of the Aeonium and the finger jade. Despite this the plants are doing well and have grow much since I got them.
I also have another pest I have found in the same planter which are found on the torch cactus and finger jade - these flattish kinda eye shaped or almond shape the smaller ones tend to be reddish and the larger ones are white. I have only found them on the finger jade mostly but when I first discovered I had a pest problem there were three white ones on the torch cactus one of which had formed a cocoon or spiderwebbing around it. This is the only instance I have seen of this webbing/cocooning.
I have been looking for an identification for these pest for a few months now and have not been able to pin point them.
I used Schults insecticide on the soil pests and they are no longer seen around the planter. A few weeks later I dug around the base of the plant and found some hiding under a dried stump like piece of the finger jade which came off and around the Aeonium.
I sprayed them and haven't seen any since but this was only a week or two ago. Thank you for your time and I hope someone can help.
Drought Smart Plants reply:
Hi Anja - what you have sounds like one of the very few pests that succulent plants are susceptible to - the mealy bug. Luckily, it is likely that you've caught it in time as your plants aren't showing signs of stress yet.
These pale pink to grey bugs cover themselves with the white waxy cotton like substance as they prepare to breed. The reddish ones you have seen will be the young. Occasionally, ones with wings will emerge, so they will spread to other plants.
They can be dealt with, but now you've had them you have to very carefully inspect every nook and cranny of every plant, especially at the soil line, in leaf axils and the growing point where the new buds will start.
To deal with them, you can find beneficial beetles mail order - look for one called Cryptolameus montrouziieri commonly called 'crypto' which is a predator that feeds on the mealy bug.
They are not as useful against the root mealy bug, so you may have to try beneficial nematodes for these as they are the only thing that will travel in the soil looking for its prey.
If you're not keen on introducing any more insects into your home, look for neem oil sprays, or a horticultural oil mixed with insecticidal soap. These only work if you are religious about repeat spraying, getting the mixture into all the hiding places.
Other sprays you can try are homemade concoctions such as hot pepper wax insect repellent, which will help protect the plant from re-infestation as well.
Rubbing alcohol is one of the older methods of getting rid of mealy bugs - make sure you test a leaf with this first as it can burn - then you may have got rid of the pest, but your plant will be dead too!
Jacki
