Help Wanted: How and When to Cut Back?

My Dad likes to say, "Dates on the calendar are closer than they appear."

Spring will be here before you know it. This past week, we finally got our first real stretch of above average temperatures with highs in the 60s. I know it won't be long before lots of plants start putting on new growth.

Before that happens, I'm aware that I probably should do some trimming. But I confess that I'm not confident I know exactly how or when to trim. Thus I humbly solicit the expertise of other more experienced gardeners on the following plants. Your advice is greatly appreciated!

Muhlenbergia capillaris, Pink Muhly Grass, Sweetgrass - Some online sources suggest cutting Pink Mulhy grass to 6-inches tall in the early spring. Other sources say that Pink Muhly should never be cut shorter than 12-inches tall, or should be cut back by one-third or even left untrimmed with the old foliage just raked out if desired. You can see why I could use some guidance here from gardeners who have grown this plant.

Schizachyrium scoparium, Little Bluestem, "The Blues" - I was dubious when a landscaper suggested these plants, but I'm oh-so-glad I agreed. This tiny little 'meadow' of waving grasses has been one of the happiest sites in my garden year-round since it was installed. Color me impressed with these golden blues. My landscaper may cut the Little Bluestem for me, but I'd still like to know what y'all think. I think I've heard that Little Bluestem should be cut to around 8-inches tall in late winter or early spring. Does that sound right to you? Or should I just rake/pull out any loose leaves?

Epimedium x perralchicum "Frohnleiten" -- An evergreen perennial with groundcover habit, I've read in the AHS Encyclopedia of Garden Plants that it's often a good idea to clip back old epimedium foliage in late winter or early spring to stimulate flowering and the growth of new foliage. Does this align with your experience? And how do epimediums typically deal with transplantation of I wanted to try moving it someplace a little shadier? (It gets lots of shade in the winter where it is now, but it has to cope with the strong afternoon sun in summertime.)

Dryopteris x australis, Dixie Wood Fern - This is a native Southeast fern that did great last year. As you can see, in winter the stems all collapsed, but the fronds stayed green. I don't have much experience with ferns, but I guess I'm just wondering whether I should cut the fronds at the base where they've already fallen to make way for new fronds in the springtime, or whether I should just let them naturally decompose as they seemed to do regularly during the warmer months last year. (I'm predisposed to just let them be.) But if I were to trim away the old fronds, should I do so now or wait until a bit later in the spring? (I'm not sure when the new fronds typically emerge...)

Finally, there's the question of Aucuba japonica or Gold Dust Plant. I'm probably zone-pushing a little with this plant, but MSU does call it hardy to -5 Fahrenheit. In a sheltered spot, it seems to have come through the harsh winter of 2013-14 (official low temperature of -2) without too much damage. Some leaves have blackened, however. Should I trim those off or will they just fall away naturally and decompose?

I'm most worried about the top part of the plant. Aucuba leaves tend to droop in cold weather and then perk up again when temperatures warm. But the leaves at the top of this Aucuba are staying droopy. And I don't see any new leaves emerging here as they are elsewhere on the plant. Should I trim off this top section or will that permanently stunt the Aucuba's growth?

Just another pic to show the new leaves emerging elsewhere on the Aucuba that I don't see at the top of the plant. From what I understand, Aucubas typically respond well to pruning. Pennsylvania garden writer George Weigel says that the tips of cold-damaged stems can be snipped off in late March just before new growth begins. Does that jibe with your experience?

Thanks for any advice or suggestions you may have. It's always nice when we gardeners can benefit from one another's experiences!

A Hard Winter, A Lot of Damage, A Little Hope

This has been a hard winter in Tennessee.

For the first time in years, the mercury dipped below zero degrees (-2 was the lowest I saw) and we had several nights in the zero to 5 degree range.

The lack of insulating snow cover and gusty breezes in my windswept hilltop garden compounded the impact of the cold temperatures.

The result? Zone-pushing plants took a real hit -- and even some broadleaf evergreens that should have been OK in my zone (like Sarcococca confusa) seem to have been killed or severely wounded.

After singing the praises of camellias in previous years, now I'm faced with the hard truth that they are only marginally hardy in Middle Tennessee.

A young camellia that I planted in November in a windy, relatively sunny spot seems to have suffered severe damage. 

Even this established camellia in a shadier and slightly more sheltered spot seems to have damage on about half its foliage.

And then there's Raphiolepsis umbellata, a.k.a. Indian Hawthorn. There were three of these in the back foundation bed (SW exposure) when we moved in. Native to India and Southern China, these members of the rose family are champs when it comes to tolerating heat and drought. They barely blinked and certainly did not wilt even when temperatures regularly soared past 100 degrees during the summer of 2012. Wind and humidity didn't faze them. Rabbits and deer didn't bother them. But the cold seems to have got the better of them.

Even the most cold-tolerant varieties are only rated as being hardy to 5 degrees Fahrenheit, and we've fallen below that number a couple of times this winter. I'm seeing what looks like significant foliage damage on all three Hawthorns. Of course, having never dealt with this before, I don't know whether the plants will shed their leaves in the spring and grow new ones, or whether they're not long for this world.

Indian Hawthorn in happier times (July 2013)

A toasted Indian Hawthorn in February 2014. Not looking promising...

Here are some photos of a few other plants that are not looking their best:

Ajuga reptans - Looks awful, but since it is rated as being hardy to zone 4, I presume it will bounce back

Ajuga genevensis - Much less common but a zone hardier than A. reptans, looks relatively thick, lush and unperturbed by zero degree temps.

Rubus calycinoides, Creeping Raspberry looking crispy. Hopefully this one will bounce back. It's rated to zone 6, but it's in a sunny, windy spot where it probably faced unusually high winter stress.

Stachys byzantina, Helene von Stein, Lamb's Ear - Most of this looks dead, but rated as hardy to zone 4, so I'm hoping it's just playing possum. There's a bit of fresh new growth peaking out from under the rubble of last year's leaves. The question is: Do I need to rake away the old growth this spring, or should I let it stay and decompose as mulch/fertilizer?

Veronica peduncularis, Prostrate Speedwell "Georgia Blue" - Looking fairly dreadful, but rated as hardy to zone 4 or 5, so again, I'm hoping this will bounce back as the weather warms.

What about the deciduous plants like crape myrtle, vitex, rose of sharon, fothergilla, chokeberry or redbud? Any damage they've suffered in these cold spells won't be visible for months until the plants leaf out (or not). I'll try to post an update when that happens.

It's hard not to get discouraged seeing how poorly some of the new and established plants have fared in this hard winter. But gardening teaches humility. I've gone back to the drawing board a bit this winter, scratching some ideas off the list and trying to find others that can withstand whatever heat, cold, floods or drought Tennessee's climate can throw at them!


So....where does the Hope come in?

Well, I did add two new shrubs to the garden that have impressed me so far with their toughness:

Juniperus virginiana "Grey Owl" -- rated to zone 2, this charming evergreen with a soft grey-green color has seemed fairly unperturbed, which is no real surprise as it's rated hardy to zone 2. Supposed to eventually reach 3-feet high by 6-feet wide, I'm considering getting several more as replacements for the Indian Hawthorns. As an Eastern Red Cedar, it's native to Tennessee, which is another plus in my book. 

Viburnum x rhytidophylloides --  Yes, the Latin name is daunting. And the 'common' name of Lantanaphyllum Viburnum really isn't that much friendlier. But last November, I bought and planted the pronounceable and esteemed "Allegheny" variety, which is supposedly more resistant to bacterial leaf spot than the species. (Always a good thing.) Allegheny viburnum is supposed to tolerate drought, pollution and heat. Thrown into the crucible its first winter in the ground, I can report that it has held onto at least a few of its leaves, which turned a lovely purplish color. And it's very encouraging to see the new baby leaves taking shape at a time when there are not many other signs of life in the garden.

So hope does spring eternal!

A maple branch starts to color up against a bright blue sky on a clear and seasonable February day.