What am I supposed to do with all my dead perennial plants in winter?

YES- definietly wait until they are brown & crispy the plants dying back sends needed nutients into root systems. Yes water weekly(maybe 2 wks depends on soil/clay content & moisture you get) and thoroughly since it's so dry where you are. I don't remove any of the dead matter in garden until spring then only so I can remove seedlings I don't want to get established. I'm in zone 9 and still have quite a few flowers, you need to add Zinnias,yellow,white & purple varietyCosmos,Marigold for fall color amoungst your perennials. These all reseed themselves and pretty much grow in my garden year round you can also put some Pansies,Mums in for some color. Also consider Freesia bulbs they are so fragrant I love them and mine this time of year are about 10-12" tall no flowers but the spikes of greenery thru out garden is nice. I still have greenery from Daylilies,Rosemary & Sweet Marjoram too.

Hello Katt,

Putting your garden to bed properly will result in a prettier, healthier garden next season.

That is a very thoughtful question. Prevention of troublesome diseases and can be effective way to have a healthier and beautiful garden the next season.

I tend to clean up most of my garden as I don’t want to give any chance for moldy type diseases to overwinter for next season. I do leave my coneflowers and my tall grasses ( miscanthius) for winter interest and the birds seem to enjoy them, removing them early spring before new growth begins.

Heres helpful links with more detailed information that might give you some pointers. Happy gardening I hope this helps!

https://www.thespruce.com/perennial-plants-to-cut-back-in-the-fall-1402712

https://extension.illinois.edu/gardenerscorner/issue_02/fall_07_05.cfm

http://fafard.com/fall-garden-cleanup/

https://www.hometalk.com/diy/grow/getting-the-yard-and-garden-ready-for-winter-39301316

Chances are you are not watering enough. I deadhead and trim constantly, as in almost every day I spent 15 minutes to a half hour checking on things and deadheading. Each plant has different needs, tell us what you have so we can offer better suggestions. I am in zone 9 and a lot of things won't grow here but there are lots of things that grow here that won't grow elsewhere. Last rain we had was April and first rain was the day before Thanksgiving, and then again yesterday. I typically have to water year round.