I'd be cautious about Neem in this warm weather we've been having. I don't know about you, but here on the Ventura Co. Coast, we've had temps in the 80's, and I think in those conditions you can count on neem burning your foliage.

I've done it, and it did. Beside that, Neem will also zap your beneficials.

I've got a few spider mites myself, but I think until the weather cools, I'll just soldier along with the garden hose until the temperatures drop down into the lower 70's. This is the best sort of weather for doing that -- it's a pleasure to go out and play with a garden hose.

Jeri

Lyda wants to be big, as you already discovered. Every summur my Lyda tries to colonize the neighbor's apple tree, pretending she is a rambler. I prune her to approx 5x5 every spring and then one more time in the middle of summer I shorten the longest canes by approx.1/3. She responds very well. Lots of blooms, no hard feelings..
Olga

My Lyda Rose is always the first to get spider mites, and always has the worst infestation. I don't know if it is just my garden, or if this is a common problem. Does anyone else have this situation?

Phil, I don't have this issue. But I wash the leaves on all my roses with a strong stream of water quite frequently and don't use insecticides.
Bayer drench contains insecticide imidacoprid, not a miticide. According to the reference below "Soil applications of the systemic insecticide imidacloprid (Merit, Marathon) have also contributed to some spider mite outbreaks".
Olga

Here is a link that might be useful: spider mites

My Lyda Rose came from Loubert in France in April and is still in a pot. It's an uncommon rose in Europe but Peter Beales carries it and says it will only be 90 cm so I thought of putting such a neat little rose between Stanwell Perpetual and Frau Karl Druschki to match both the white of Frau Karl and the pale pink of Stanwell. Perhaps I have to reconsider where to put Lyda Rose although I cannot expect it to reach Californian heights! Can anyone from a colder climate give me an idea of what I can expect? Mine is already about 90 centimetres tall.

Mariannes, I am in zone 6B and on the east coast, so nothing similar to CA. I would say 6-8 feet around. The height could be much more(8-10) if you don't shorten the longest canes.
Olga

I'm afraid to find a growing season similar to Mariannese's, we'd need to hear from Vancouver Island.

Spidermites: I had two bushes infested earlier - short floribundas in a prime (hot, dry) location. All the dwarf alberta spruce had spider mites also.

I sprayed once with TetraSan 5 from Rosemania. I sprayed the whole garden in part because I had lost one rose to Rose Rosette. One spraying did it - all species of plant life made a quick recovery. I know the roses had red spider mites, the spruce another type. The TetraSan handled both.

I have since added some of those water crystals to the soil under the two floribundas that were infested to help maintain some humidity. Short roses in hot locations seem particularly prone to spider mite infestations. I taught DH to spray down the spruce thoroughly every time he waters or has the hose out for something. I don't know what it is with those dwarf spruce though - they all have nice locations, nice soil, heavy mulch. I think they are just annoying me cause DH likes them and I don't.

My 7-8 yr old Lyda has arching canes about 5 feet long - very mannerly. The only pruning I do is to cut off the huge panicles of blooms for use in arrangements. No spider mites here, but I don't use pesticides so maybe beneficials keep them in check? Mine is planted in 4-5 hrs of sun, maybe mites prefer sun/heat?

My neighbor has a 5 year old, own root Lyda rose which is less than 4 feet tall.
Luxrosa

Jeri, it has not been that hot here the last few days. We may have seen one or two days last week in the 80's, but the last few days have been low to mid 70's. I am closer to the beach (about a mile) than you I think. Nevertheless, I used the jetspray nozzle again today. Hopefully, I can knock the population down a bit this way. Before the Bayer, I had never used a stronger pesticide than Neem or Safer soap. I have learned my lesson!

I had no idea Lyda Rose got so big! I should know better that anything I grow here gets twice as big as anywhere else. Usually I automatically add a few feet to the height posted at Helpmefind. Olga, I take it that you are saying it would be okay to give her a pruning now? She is blooming nonstop despite the spidermite infestation. If I cut her canes down now, will she still produce blooms this summer?

Yes, she will produce. At least that is what she is doing for me. By cutting down I mean shortening of the longest canes.
Olga