Question
Hello,
I live in northern Nevada about an hours drive east of Reno. Elevation is 4300 ft. I planted a small fruit orchard and want to protect it from high winds. Have already planted a row of caragana on the winward side and want to triple up the screen with a row each of mock orange and purple leaf plum hedge. As much for looks as function.I know the caragana can handle the winds but I'm not sure about the other two. The winds here can be very strong. Up to fifty miles an hour and can blow for days. Behind the hedge screen I intend to plant a row of cottonwoods.
 I planted a row of common lilacs this May to screen a large propane tank that sits out in the open and they were doing well until the heat and winds came this summer.Each plant has a basin around it and I water about every two days.The soil here is basically sand and alkaline and dries out very quickly because of the low humidity.We've had a very hot summer here and I'm hoping the lilacs wil perk up in the fall. Should I move them to a more sheltered area and plant something else? Space is not a problem. I have screens around everything edible and have temporarily gained the upper hand on the jackrabbits,cottontails,and chipmunks.
  Any suggestions would be appreciated.

 Thanks,
 Craig

Answer
Craig,
First the Lilac problem. Lilacs traditionally do not do well in zones 7 & 8, because of heat and low humidity. The soil also plays a huge role in their health. The best soils for lilacs are ones that are close to neutral and contains a high level of organic matter. You can amend the soil around your plants by adding peat moss, leaf litter compost and a high quality topsoil. Mulching is also important to help lock moisture into the soil around the plants. Fertilize them this fall with a low nitrogen high phosphorous and potassium fertilizer to build up their root systems. Most importantly, keep them well watered through the summer months.
As far as wind resistance for the Mockorange and Plum, They will do as well as any other plants under those conditions. Both are not very fragile trees and should stand up well- especially if you will be sheilding them with cottonwods.
Good luck.
Ed Gulliksen