I lived in Las Vegas for 6 years, I had roses. They are surprisingly
easy to grow in LV.
I didn't find one web site that lists all flowering plants for the
area, ...I found several mentions of beautiful flowering plants that
grow in Las Vegas at different sites.
I would send her here:
Reasonable prices, helpful staff. They don't have anything that WON'T
grow in Las Vegas. Read below to see the considerations before
buying. She has some decisions to make before going to a nursery.
What kind of plants are best for my yard? (Most often asked by people
new to the area, but not asked often enough before purchase.)
..."Before this question can be answered, other things must be
considered! Where are you going to plant it- -south, west, east or
north exposure; near a reflected heat source like a west-facing wall?
Will it be exposed to strong, drying winds, either hot or cold? Will
it be subjected to lawn water or sprinkler overspray? Will it
withstand frost and freezing temperatures? Understand the sun, shade,
and water requirements of your plant selection before you plant it!
Browse your local nursery or garden center and read the signs. Ask a
sales associate for specific information if you're not sure, and ask
for any literature that may be available. With this information,
you'll be able to pick plants that will complement your landscape and
more importantly will stand a greater chance of survival. Star Note
535 has a list of recommended plants for hot, dry climates. Folks in
other parts of the country can also check with their University
Cooperative Extension Services for ideas..."
STAR NOTE 535 (mentioned above):
Local experts pick their favorite plants
Las Vegas - Gardening Survival Guide
Check out other links on the left...
new desert dweller: need help knowing what to plant
Many plant types mentioned here.
This page is at the same site, even better info:
....'NATIVE PLANTS - Use plants that are native to the Sonoran, Mohave
or Chihuahuan deserts for best performance. These deserts are all
found in the Southwestern U.S. and in Mexico. Plants from deserts from
other continents (i.e. Africa or Australia) will usually perform well
but the look may not always fit (i.e. large Eucalyptus trees). ..."
Same site: Search results for: "Las Vegas"
Most of this page will however concentrate on a subset of the
Angiosperms: the so-called "Wildflowers" -- annual plants whose main
above-ground growth dies at the end of the growing season and which
generally lack woody stems.
SONORAN DESERT PLANTS - SEASONAL FLOWERING SCHEDULES
If you'd like a few more links, or more help, just ask in a clarification.