Thank you Alberto, great clarification about climates which I am struggling to understand. Also for the compliment, but my growing efforts in the past twenty years have primarily been with alpine, Mediterranean, and cold Winter growing continental bulbs in pots. Exploring their climatic limitations and requirements. I have made no systematic set of experiments with insecticides or other horticultural chemicals other than a few fertilisers. I am also still a novice with Summer and warm climate bulbs. They require very different conditions! From what you say about these Andean slopes being hot dry and stony - I often tell people wanting to grow plants from Cyclamen graecum to Fritillaria gibbosa -dry climate or dessert 'bulbs', that the first thing I would do in a dessert is get under the nearest rock to shelter from the heat or cold. So such plants actually prefer a deeply buried root system which does not get too hot and dry, (though it may be highly aerated). This is a lesson which I have learned from cold temperate bulbs( winter growing). It does not always hold good for warmer and many southern hemisphere climates. However, perhaps it fits the model for Paramongia -and some Rhodophialia? One might think that the alkaloids in the Amarylidacea might kill any grub, but alas, no. I have read discouraging articles which suggest chemicals now available on the amateur market in the UK have little effect on this pest. The usual successful method, (which I have not had time to implement yet), is to net all doors and vents in the glass house. Usually if a plant can be kept happy, pests are less likely to attack. Narcissus fly does not adhere to this rule. (nor do aphids on Onco Iris) I use soap on aphids most of the time and occasionally drench with other insecticides at rare and opportune moments if necessary. I prefer to maintain a natural soil as much as possible though. The plants may be protected by sterile conditions but they seem to grow more strongly in a more natural environment. - Remember recent posts on leaf-mould? I have tried Provado and a couple of others against narcissus fly but not regularly enough to know if it helps. On Fri, Jan 31, 2014 at 12:13 AM, Alberto <ezeizabotgard@hotmail.com> wrote: > Not from the lomas but from Andean west facing slopes in a very hot > habitat. Not alpines. Temperatures more for a Hippeastrum than for a > Meconopsis. People that have been there during the flowering season report > the tremendous heat. Incidentally the plants grow in exposed spots in full > sun, as mentioned. > > In the lomas the first part of winter is dry and the growing/rainy season > is very short: June, July, August, (southern emisphere), perhaps September. > More (normal to us) rainy seasons have reported as having a very adverse > effect on seed production therefore the lomas bulbs must be grown very dry > more like a cactus. > > For dry semidesertic plants ventilation (forced, that is) is most > important. > > Peter, you are one of the top experts of the world in the field of bulbs. > I have often wondered why people do not use a systemic insecticide drench > on those growing bulbs susceptible to the fly attack. It seems impossible > that a grub could feed on poisoned tissue. > >