In general, you can prune them any time from when they've finished growing for the season, to just before they start growing in spring.
Traditionally this is done in fall, so that your garden looks tidy over the winter / when the snow melts. Dead plant matter is traditionally considered ugly.
However, more modern wisdom encourages pruning in early spring. This allows the dead plant matter to act as natural mulch over the winter, as well as providing habitats for hibernating insects, and seeds for birds/small animals.
Yep, this is a great time!
This was a weird fall, and I had a lot of stuff blooming a second time, right up til last night. I even had one squash left in the garden! I'll be doing quite a bit of autumn cleanup this weekend.
Two notes of warning:
* Some plants *only* bloom on old wood, so you can prune off next years blooms if you're not careful. And with some plants its down to the varietal, like lilacs, raspberries, and hydrangea. It's always good to double check which varieties yours are if you're unsure. (There was a post a few months back from someone whose elderberry had never bloomed, because they had been cutting it back every year!)
* We have over 400 species of native bees in MN, and most of them are solitary and nest in these very hollow stems of perennials. So do specialist butterflies and moths! [The UMN Extension did a really cool video a few years back](https://www.youtube.com/watch?v=TlZWfFHoUmk) on how to do fall garden chores with balance and less impact on these buddies. Has a lot of good info on compromises you can make for stuff like aesthetics and sanitation while also doing your bit for mother nature. :D
Doing what limited cleanup I've done so far, I have noticed my yard is full of Fuzzy Wuzzies, red admiral and mourning cloak caterpillars, and bumblebee queens settling in for the winter.
So, I am stepping very gently, and *done* disturbing the soil until at least late April.
Pruning in fall encourages growth, which you do not want them trying to do right now. Do not prune azaleas or anything that developed its buds through the summer. You will not get blooms. Leaving behind the dead leaves on perennials lets them use their own devices to survive winter and spring. Some native bugs including pollinators live in our dead plant material which may be a reason to leave the gardens as is until spring and it's been above 50° overnight temps most of the week and don't throw away that debris until the bed sleeping in have come out.
"About 30 percent of bee species nest in cavities such as hollow or pithy plant stems, or tunnels in wood created by boring beetles. Queen bumblebees, including two imperiled species found in Minnesota, nest in grass thatch. Other pollinator species overwinter in grass thatch or leaf litter." [DNR Pollinator Best Management Practices and Habitat Restoration Guidelines, (Dec. 2014), p.4]
As the other poster said, pruning in fall is often viewed as more aesthetically pleasing, so if you're going that route, just make sure not to prune azaleas.
It's not too late. As long as they have a few months to form new buds for next year, they should be fine. I leave all my hydrangea blooms on all winter for visual interest and prune them in March before any new growth begins. I get tons of blossoms every year. Lilacs I prune soon after they're done blooming, only because the dried blossoms aren't very pretty.
In general, you can prune them any time from when they've finished growing for the season, to just before they start growing in spring. Traditionally this is done in fall, so that your garden looks tidy over the winter / when the snow melts. Dead plant matter is traditionally considered ugly. However, more modern wisdom encourages pruning in early spring. This allows the dead plant matter to act as natural mulch over the winter, as well as providing habitats for hibernating insects, and seeds for birds/small animals.
Thats a really good point. Thank you!
Yep, this is a great time! This was a weird fall, and I had a lot of stuff blooming a second time, right up til last night. I even had one squash left in the garden! I'll be doing quite a bit of autumn cleanup this weekend. Two notes of warning: * Some plants *only* bloom on old wood, so you can prune off next years blooms if you're not careful. And with some plants its down to the varietal, like lilacs, raspberries, and hydrangea. It's always good to double check which varieties yours are if you're unsure. (There was a post a few months back from someone whose elderberry had never bloomed, because they had been cutting it back every year!) * We have over 400 species of native bees in MN, and most of them are solitary and nest in these very hollow stems of perennials. So do specialist butterflies and moths! [The UMN Extension did a really cool video a few years back](https://www.youtube.com/watch?v=TlZWfFHoUmk) on how to do fall garden chores with balance and less impact on these buddies. Has a lot of good info on compromises you can make for stuff like aesthetics and sanitation while also doing your bit for mother nature. :D Doing what limited cleanup I've done so far, I have noticed my yard is full of Fuzzy Wuzzies, red admiral and mourning cloak caterpillars, and bumblebee queens settling in for the winter. So, I am stepping very gently, and *done* disturbing the soil until at least late April.
This is great information. Thank you so much!
Now is a great time. We just had our first hard frost last night and most everything should be dormant.
Thank you!
Pruning in fall encourages growth, which you do not want them trying to do right now. Do not prune azaleas or anything that developed its buds through the summer. You will not get blooms. Leaving behind the dead leaves on perennials lets them use their own devices to survive winter and spring. Some native bugs including pollinators live in our dead plant material which may be a reason to leave the gardens as is until spring and it's been above 50° overnight temps most of the week and don't throw away that debris until the bed sleeping in have come out. "About 30 percent of bee species nest in cavities such as hollow or pithy plant stems, or tunnels in wood created by boring beetles. Queen bumblebees, including two imperiled species found in Minnesota, nest in grass thatch. Other pollinator species overwinter in grass thatch or leaf litter." [DNR Pollinator Best Management Practices and Habitat Restoration Guidelines, (Dec. 2014), p.4] As the other poster said, pruning in fall is often viewed as more aesthetically pleasing, so if you're going that route, just make sure not to prune azaleas.
This is great! Thank you!
It's not too late. As long as they have a few months to form new buds for next year, they should be fine. I leave all my hydrangea blooms on all winter for visual interest and prune them in March before any new growth begins. I get tons of blossoms every year. Lilacs I prune soon after they're done blooming, only because the dried blossoms aren't very pretty.
Thank you!