Wednesday, April 23, 2014

So What's the Damage?

Alchemilla mollis, Lady's Mantle, unhurt by a late freeze, looking bigger and better than ever this year.
Alchemilla mollis, Lady's Mantle, unhurt by a late freeze, looking bigger and better than ever this year.


The Details:

The weekend of April 12th, temperatures topped out near 80 degrees (Fahrenheit). Then a cold front came crashing through - two nights in the mid-30s and one night where temperatures dipped all the way to 28 degrees Fahrenheit in our neighborhood. (I foreshadowed this cold snap in a blog post last week.)

In true Darwinian style, I left most plants uncovered and unprotected to fend for themselves.

Remarkably and encouragingly, most pulled through without any problems. Here's a list of the ones that laughed off the cold and the few where winter got the last laugh.


Little or No Damage:

- Agastache foeniculum, Golden Jubilee
- Ajuga genevensis (leaves and flowers both unharmed)
- Alchemilla mollis
- Aronia, Chokeberry (buds, flowers and leaves all unharmed)
- Athyrium nipponicum, Japanese Painted Fern (newly planted)
- Baptisia australis (covered with an overturned pot for protection)
- Cercis canadensis, Redbud (flowers and emerging foliage both appear unharmed)
- Chrysogonum virginianum, Green and Gold

Chrysogonum virginianum, Green and Gold, undamaged by the cold, now bursting into bloom.
Chrysogonum virginianum, Green and Gold, undamaged by the cold, now bursting into bloom.

- Clematis "Crystal Fountain" (leaves and buds both appear unharmed)
- Cranesbill Geraniums (Biokovo, Rozanne and sanguineum)
- Dianthus gratianopolitanus "Firewitch"
- Echinacea purpurea
- Fothergilla gardenii (leaves appear unharmed, some flowers may have been damaged, others seem to be fine)
- Gaillardia x grandiflora "Arizona Apricot"
- Helianthus "Lemon Queen" perennial sunflower
- Hemerocallis, Daylilies
- Hydrangea quercifolia, Oakleaf Hydrangea

Hydrangea quercifolia, Oakleaf Hydrangea, seemed unfazed by the cold. I planted this shrub in autumn 2012 and did not see any flowers last year. Maybe this is the beginning of a flower panicle?!
Hydrangea quercifolia, Oakleaf Hydrangea, seemed unfazed by the cold. I planted this shrub in autumn 2012 and did not see any flowers last year. Maybe this is the beginning of a flower panicle?!


- Hypericum frondosum "Sunburst"
- Juniperus virginiana, Brodie, Burkii and Grey Owl varieties
- Lavandula, Lavender, "Hidcote" (newly planted)
- Liatris spicata
- Liriope muscari (newly planted)
- Lonicera sempervirens, Coral Honeysuckle (leaves, buds and flowers)
- Malus, Crabapple, "SugarTyme" variety (leaves seem fine, flowers were pretty much finished blooming anyway, so it's hard to gauge whether they would have been damaged)
- Panicum virgatum, Switchgrass, "Northwind" (covered one clump with an overturned pot, but new growth on both protected and unprotected clumps seems equally unharmed)
- Philadelphus x virginalis, Mock Orange, "Natchez" (leaves and buds both seem unharmed)

Philadelphus x virginalis, Mock Orange, Natchez variety, leaves and buds appear totally undamaged by last week's cold snap
Philadelphus x virginalis, Mock Orange, Natchez variety, leaves and buds appear totally undamaged by last week's cold snap

- Phlox paniculata
- Platycodon, Balloon Flower (covered one clump with an overturned pot, but the control clump that was not covered looks fine too)
- Polystichum acrostichoides, Christmas Fern (newly planted)
- Rhus aromatica, Fragrant Sumac, "Gro-Low" (buds seem fine, there may be a little foliar damage on some emerging leaves, but I think the majority of emerging foliage seems fine at this point)

Rhus aromatic "Gro-Low" Sumac does not seem to have been set back at all by the freeze
Rhus aromatic "Gro-Low" Sumac does not seem to have been set back at all by the freeze. Check out those beautiful lemon yellow buds and fresh multicolored foliage! I'm enraptured!!

- Stachys byzantina, Lamb's Ear, "Helene von Stein"
- Veronica umbrosa, Prostrate Speedwell, "Georgia Blue" (leaves and flowers both seem unharmed)
- Viburnum prunifolium, Blackhaw (buds and open flowers both seem unharmed)
- Viburnum x pragense, Prague (buds and open flowers both seem unharmed)

Neither the new leaves nor the flowers on the Prague Viburnums were damaged by the late freeze
Neither the new leaves nor the flowers on the Prague Viburnums were damaged by the late freeze

- Viburnum rhytidophylloides, Alleghany variety (perhaps a little foliage damage on some plants, another seems unharmed)



Moderate damage:

- Agastache rugosa, Honey Bee Blue (perhaps 30% of foliage seems damaged/killed on newly installed plants)
- Aucuba japonica (established leaves seem fine, some of the of emerging new growth may have been damaged)
- Buxus sempervirens, Hardy Boxwood (established leaves seem fine, but new growth seems limp and damaged, I suspect I'll need to break out the pruning shears and give the Boxwoods a haircut back to healthy growth)

Wilted and whitened foliage marks frost and/or freeze damage on a Boxwood (Buxus)
Wilted and whitened foliage marks frost and/or freeze damage on a Boxwood (Buxus)


- Cephalotaxus harringtonia, Japanese Plum Yew, "Prostrata" (established foliage seems fine, it looks as though the new growth may have been damaged, but I'm not familiar enough with this newly-installed plant to diagnose the degree of damage with any certainty)


Major damage:

- Ceratostigma plumbaginoides, Leadwort Blue Plumbago (newly emerging foliage seems limp, dark brown and dead)
- Hibiscus syriacus, Rose of Sharon (newly emerging foliage and young leaves on both Rose of Sharons looks limp and dead)

Newly emerging foliage got fried on this Blue Bird Rose of Sharon.  This photo was taken about a week after the cold snap.
Newly emerging foliage got fried on this Blue Bird Rose of Sharon.
This photo was taken about a week after the cold snap. 


- Lagerstroemia indica, Crape Myrtle (most newly emerging foliage looks dead and blackened, fortunately several trees had not yet started to leaf out, interestingly foliage on a few branches of one Natchez crape seems fine, even though foliage on other branches seems dead!)

Luckily not much foliage had emerged before the cold snap on the crape myrtles, which are some of the latest trees here to leaf out. The leaves on this branch that had started emerging seem to be toast. All the green leaves in the background were still dormant buds during the freeze and have just awakened and put out green foliage in the past few days.
Crape myrtle with frozen dead leaves and fresh green leaves on different branches

- Vitex agnus-castus, Chaste Tree (newly emerging foliage appears to have been totally killed)

Vitex agnus-castus foliage appears to have bitten the dust.
No sign of any new foliage yet in the week since the freeze.


So that's the story.

Overall, I was very pleased with the way most plants pulled through.

Monday, April 14, 2014

Winter Gets in One More Punch

Screenshot from NOAA

Uh oh.

Tonight's forecast low is 39 degrees Fahrenheit.

Tomorrow night we're expected to drop to 29.

Wednesday night could see a chilly 38.


It's the frosty Tuesday night forecast that's got me concerned. The warm weather over the past few days (temperatures around 80 degrees Friday, Saturday and Sunday) induced many of the plants that had stayed safely dormant through an interminable winter to unfurl new leaves and flowers.


Fothergilla in full bloom. Will these flowers withstand a brief spell at 29 degrees?
Fothergilla in full bloom. Will these flowers withstand a brief spell at 29 degrees?

I'm worried there will be significant damage to all this tender new growth if and when temps dip below freezing tomorrow night.

Creamy nodding aquilegia flowers come have started to bloom
Creamy nodding aquilegia flowers come have started to bloom

New leaves on the Natchez crape myrtle
New leaves on the Natchez crape myrtle, one of the last trees in our area to leaf out.

Typically, I aspire to be a Darwinian gardener, prizing plants tough enough to survive on their own. But this time, I think I might just intervene a wee bit and use overturned clay pots to cover Balloon Flower and Baptisia australis.

Fresh bright green growth on Balloon Flower (Platycodon)
Fresh bright green growth on Balloon Flower (Platycodon). I think I will try covering this plant with an overturned pot tomorrow afternoon to retain some heat overnight.


Do you have any experience with late frosts and freezes? 

If so, which of your plants have come through unscathed and which have suffered major (or minor) damage?

I took lots more photos this evening. Stay tuned for another post toward the end of this week showing which plants sailed through without a scratch and which ones took it on the chin.

Sunday, April 13, 2014

Tulip Extravaganza! (And Dogwoods too)

This morning we visited Cheekwood Botanical Gardens in Nashville.

Cheekwood has been going all out with tulips the last couple of years. Last year, they claimed 50,000 bulbs. This year, they upped the ante and doubled the count to a neat 100,000!

Here are some highlights from our visit - plenty of tulips, but also some dogwoods and ...

Yellow tulip with violas


River of orange tulips
River of orange 

Blowzy pink and purple tulips

Pink and lavender tulips surround a gazebo
What a lovely spot for a rendezvous...


White, pink and purple tulips mixed with blue and yellow violas
So many colors -- somehow they all work beautifully together!

White tulips mixed with purple fringed tulips
Who doesn't love a fringed purple tulip?

River of white and purple tulips flows beneath still bare mature crape myrtle trees
These majestic mature crape myrtle trees may still be bare, but their exfoliated trunks serve as the perfect vertical contrast to this flowing river of white and purple tulips

A patch of cheerful yellow tulips
What a sunny, cheerful sight!

Yellow and orange formal tulips surround a billowy informal yellow variety
Here's an unusual "deconstructed" yellow tulip surrounded by some complementary more formal peers


And it wasn't all about the tulips at Cheekwood. The garden has an impressive collection of dogwoods, many of which were in bloom. Our favorite was Cherokee Chief:

Cornus florida "Cherokee Chief" Dogwood
Cornus florida "Cherokee Chief" Dogwood

Cornus florida "Xanthocarpa" full of white flowers
Cornus florida "Xanthocarpa"


Cornus florida "Xanthocarpa" flowers against a blue April sky
Cornus florida "Xanthocarpa" flowers against a blue April sky

Side-by-side pink and white flowering dogwood trees seem to enhance each other's beauty
Side-by-side pink and white flowering dogwood trees seem to enhance each other's beauty

Friday, April 11, 2014

Rhapsody in Blue

Veronica  peduncularis "Georgia Blue" in glorious full bloom on April 9, 2014

Georgia Blue's foliage burned considerably over this harsh 2013-14 winter, and I toyed with the idea of shovel-pruning it and chalking it up as another gardening trial-and-error.

What a colossal dunderhead move that would have been!

Luckily, I bided my time and Veronica rewarded my patience with the foliage recovering at a stunning pace. (In fact, I didn't even have to remove any of the dead foliage as it quickly decayed and/or was covered up by new growth.)

Now I'm so smitten that I'm planning to add a couple more Georgia Blues in the same spot!

Wednesday, April 9, 2014

Creeping Raspberry, Inflated Expectations and Beautiful Treasures

Creeping raspberry vines do not appreciate -2 Fahrenheit temperatures. This plant seems to have died back to the roots and the new foliage is emerging from below ground.
Creeping raspberry vines do not appreciate -2 Fahrenheit temperatures. This plant seems to have died back to the roots and the new foliage is emerging from below ground.


Do you ever have a plant that crushes your hopes and dreams?

OK, maybe that's a little melodramatic, but I was sure I'd found the groundcover of my dreams when I read descriptions of Creeping Raspberry or Crinkle-Leaf Creeper (a.k.a. Rubus hayata-koidzumii, Rubus calycinoides or Rubus pentalobus). I should have known better than to trust a plant with so many aliases!

I was under the impression that Creeping Raspberry would make a solid weed-suppressing evergreen groundcover with the benefit of some flowers and even a few edible berries in springtime. It did relatively well in my garden last year - well enough for me to add another plant last autumn.

I should have known better.

Reviewing my sources, I see that the people and organizations praising Creeping Raspberry as an evergreen groundcover are one to one-and-a-half zones warmer than me gardening in places like Statesboro, Georgia (zone 8a) and Clemson, South Carolina (zone 8a).

Here in my zone 6b/7a garden (low temperature -2 Fahrenheit this past winter with no insulating snowcover to soften the blow), Creeping Raspberry apparently acts like an herbaceous perennial - dying back to the roots and slowly emerging in early April.

Creeping Raspberry tentatively steps back onto the stage
Creeping Raspberry tentatively steps back onto the stage

Maybe I should be grateful rather than exasperated?

After all, even though some sources do list Creeping Raspberry as being hardy to zone 6, there are others that only rate the plant for zone 7 or above. Alabama's Cooperative Extension System recommends Creeping Raspberry except in the northeast corner of the state, where it acknowledges that winter hardiness can be a problem.

Well, northeast Alabama (perhaps the Huntsville area?) is still solidly in zone 7a - I'm guessing at least a few degrees warmer than my Middle Tennessee garden on most winter nights. If the extension service is worried about Creeping Raspberry surviving in Huntsville, I guess I was inadvertently pushing my luck in the Nashville area.

So, will I pull the plants from the garden? I don't think so. I think it's just a matter of recalibrating my expectations.

After all, I believe the meteorologists said last winter was the coldest winter here in 20 years. Perhaps in a gentler winter where lows dip "only" into the single digits or a warm winter where temps stay in the teens, Creeping Raspberry's vines will survive and the plant will act more like an evergreen groundcover?

And even if it does die back to the roots, how is that any worse than other groundcovers I enjoy - like Rozanne Cranesbill Geranium, Lamb's Ear or Lady's Mantle? (Although I will say that all three of these alternates spring from the ground much more quickly in the spring and all are rated to hardy to zones 4-5.)

For now, I've scrapped any plans to add additional Creeping Raspberry plants to the garden, but I do look forward to seeing how/whether the three Creeping Raspberry plants recover in 2014.

Meanwhile, I have a choice - I could be envious of all those gardeners in slightly warmer zones whose gardens are apparently better suited to so many of the plants I'd love to grow (not just Creeping Raspberry, but everything from Camellia and Choisya ternata to Loquats and Japanese Persimmons).

But gardening reminds us of an important life lesson - we can lament the things we lack, or we can be grateful for whatever beautiful treasures we are privileged to experience.

Aronia arbutifolia buds stretch out in preparation to bloom
Aronia arbutifolia buds stretch out in preparation to bloom

An unknown Camellia japonica survived the winter to bloom with exuberance
An unknown Camellia japonica survived the winter to bloom with exuberance

Native Oak Leaf Hydrangea leaves embrace the sunshine
Native Oakleaf Hydrangea (Hydrangea quercifolia "Snowflake") leaves embrace the sunshine

Sunday, April 6, 2014

Evidence of Poor Drainage

A photo is worth 1000 words:

Poor drainage: water fills a hole in the garden more than 12 hours after a heavy rainfall
More than 12 hours after a heavy rainfall...

Digging a hole and filling it with water to check how quickly the soil drains is considered a standard way to check whether you have soil compact and poor soil drainage.

I didn't intentionally dig this hole to check soil drainage. I dug it in the process or removing an Euonymous alata (a.k.a. Burning Bush), which is listed by the National Park Service as an invasive plant.

I haven't quite gotten around to figuring out what I want to plant there, but whatever it is, it had better be comfortable with periodic flooding.

I already knew the soil drainage was not great in large parts of the backyard. The yard is sloped downward toward the street in the front, so the drainage is better there, but after heavy rains, parts of the back yard can stay soggy for days. When I hired a landscaper to add some plants to the back yard this year, he showed me just how compacted and dense the soil is back there.

I believe that the problem, as in many relatively new developments, has to do with soil compaction caused by heavy machinery. Plus I imagine that the top soil may have been scraped away to sell early in the construction process, with only a thin layer of soil (probably attached to the grass sod) put down when construction was complete. I can tell you there's about a half-inch of black soil attached to the grass in the backyard and then it's heavy, sticky, thick, murderous clay as far down as you can dig.

Thus the subtitle of this blog - Adventures in Gardening on Tennessee Clay!

That being said, the drainage is not equally bad everywhere in the backyard. Perhaps 30 feet away from the hole above, I dug another hole (while removing another burning bush). As you can see below, that hole did not hold water for nearly as long after the same storms had rolled through.

Clay soil with better drainage does not hold puddles more than 12 hours after a storm
Not nearly as much water in this hole, although quite a bit of mulch has washed in

So what's the problem with poor drainage? Roots need water, but they also need oxygen. Yes, roots need to breathe! If soil stays saturated for lengths of time, roots can drown and/or rot.

There are plants that can survive in wet or continuously moist soil, but they are not usually the same plants that are able to survive drought, which is also a regular occurrence in Tennessee.

Similarly, many drought-tolerant plants require well-drained, sandy or rocky low-fertility soils, which are clearly not the prevalent conditions here.

I'm compiling a list of plants that can survive both drought and flooding (plus single-digit winter lows and above-100 summertime highs). For instance, Baptisia australis (False Indigo) reportedly can withstand both severe drought and extended flooding.

I'd love to have suggestions to add to the list!

Thursday, April 3, 2014

Sparkly, Shiny and New!

Alchemilla mollis (Lady's Mantle) leaves sparkle with raindrops on the morning after a heavy storm
Alchemilla mollis (Lady's Mantle) leaves sparkle with raindrops on the morning after a heavy storm

Shiny leaves appear on Aronia melanocarpa (Black Chokeberry)
Shiny leaves appear on Aronia melanocarpa (Black Chokeberry)

Fresh new fuzzy foliage unfurls on an Alleghany Viburnum (Viburnum x rhytidophylloides)
Fresh new fuzzy foliage unfurls on an Alleghany Viburnum (Viburnum x rhytidophylloides) 

Saturday, March 22, 2014

And They're Back!

Yellow daffodil
Daffodils have been blooming for weeks now in Middle Tennessee
The earliest blooms got felled by nights in the teens, but new flowers have taken their place

If you’re anything like me, you start looking forward to spring around, oh, January 2nd

But it’s a long, cold slog from the dawn of the New Year until many plants starting showing signs of life here on the zone 6-7 border in Middle Tennessee. Trees like Crape Myrtle and Vitex may be able to handle our summer heat, but they can take until mid-April to start leafing out. And perennials like Hardy Hibiscus can hide below ground until at least that time.

Since this winter was particularly harsh, I was worried that Spring would come late. But a stretch of temperatures in the 50s and 60s has breathed new life into the garden. 

(Note that the forecast over the next few days calls for a cold spell with lows in the lower-20s. I'll post updates of any damage. If I don't show damage, that means the plant seems to have emerged unscathed. No news equals good news in this case.)

Fuzzy new growth on an Arrowwood Viburnum
These plants sat in the garage all winter with barely any water.
I bought them too late last year (via mail order) and the weather turned brutal before I could get them in the ground.
Mea culpa. 
And yet, they survived. Color me impressed.
Alleghany Viburnum
New leaves on Alleghany Viburnum. Actually, the leaves have looked this way for weeks now.
It's my first spring with this plant, so I'm not sure if this is normal or when they'll unfurl.

"Vera Jameson" Sedum
"Vera Jameson" Sedum  

Salvia nemorosa (either May Night or Blue Hill, not sure which)
Salvia nemorosa (either May Night or Blue Hill, not sure which)

Redbud buds
Red buds on a redbud tree

Phlox paniculata "David"
Phlox paniculata "David", third year in the ground
I do like that P. paniculata emerges so early and the young leaves look beautiful.
They tend to look tired and tattered later in the summer in Middle TN.
I may try thinning out the stems this year to see if that helps improve air circulation and prevent mildew.

Phlox paniculata "Blue Boy"
Phlox paniculata "Blue Boy"
Beautiful foliage

Mock Orange, Philadelphus x virginalis "Natchez"
Mock Orange, Philadelphus x virginalis "Natchez"

Hydrangea quercifolia, Oakleaf Hydrangea "Snowflake"
Hydrangea quercifolia, Oakleaf Hydrangea "Snowflake"

Maple tree flowers
Maple tree flowers

Nigella damascena, Love in a Mist, self-sown seedling
Nigella damascena, Love in a Mist, self-sown seedling

Love in a Mist and a little Henbit
Loads of Love in a Mist (and a little Henbit, which is a weed, but a pretty one)
If you grow Love in a Mist, be aware that it can self sow enthusiastically unless seed heads are removed.
(The seed heads do stay on the plant a long time without shattering, so it should not be too hard to prevent or limit self-seeding if desired.)

Stachys byzantina, Lamb's Ear "Helene von Stein"
Stachys byzantina, Lamb's Ear "Helene von Stein"
Note that I left last year's dead leaves to decay. 
Most sources advise raking the dead leaves away in the spring, but I wanted to see what would happen if I left them. So far, the Lamb's Ear seems to be doing just fine. I hope the old leaves will decay in warm weather and provide the plant with nutrients. It's a little unsightly at the moment, but I presume the new leaves will soon cover the old foliage.

Close up of Stachys byzantina, Lamb's Ear "Helene von Stein"
Close up on the Lamb's Ear. 
Love the fuzzy foliage.


Geranium x Cantabrigiense, Cambridge Geranium "Biokovo"
Geranium x Cantabrigiense, Cambridge Geranium "Biokovo"

Juniperus virginiana "Grey Owl"
Juniperus virginiana "Grey Owl"
(I cheated here a little. There are no flowers or new leaves to show here, but this new addition to the garden performed beautifully through the cold weather and deserves a moment in the spotlight.)

Viola tricolor, Johnny Jump Up
Viola tricolor, Johnny Jump Up
I had lots of these last year, but this is the only flower I've seen so far this year. 
Hopefully more will soon appear.  


Gaillardia grandiflora “Arizona Apricot”
 Gaillardia grandiflora “Arizona Apricot”
Gaillardias reportedly are susceptible to root rot in heavy clay soils, so I wasn’t sure if this would come back at all, but it seems to have survived. (Plus you can see how poorly the plant was rooted last year. Now that it's taken root more firmly, hopefully it will perform even better in 2014.)

Forsythia
My neighbor's forsythia. All the forsythias in the neighborhood have burst into bloom in the past few days.

Daylily new foliage
Daylilies. 
As I've mentioned in other blog posts, I'm not a huge fan of daylilies for most of the year.
But I do love the exuberant fresh green foliage in early springtime!


Clematis "Crystal Fountain"
Clematis "Crystal Fountain"
I'm trying to train this clematis to climb a crape myrtle, so far with limited success.

Echinacea purpurea, Eastern Purple Coneflower
Echinacea purpurea, Eastern Purple Coneflower
I leave the seedheads standing over the winter  both to feed the birds and to help the Coneflowers multiply.
This strategy seems to be working!


Rubus calycinoides (a.k.a. Rubus pentalobus), Creeping Raspberry
Rubus calycinoides (a.k.a. Rubus pentalobus), Creeping Raspberry
I was under the impression that Creeping Raspberry was an evergreen groundcover, instead it seems to be performing like an herbaceous perennial in my zone 6/7 garden. 
This is a little disappointing. 
But I'll be patient. Perhaps the old stems will sprout new leaves later in the spring?
Anyway, it's nice to see new growth and know the plant is not dead!

Camellia buds after cold winter
Unknown camellia.
Several young camellias were severely damaged by our cold winter.
You can see that this established camellia suffered some foliage damage too. 
Still, I'm impressed it did not drop its buds. They seem poised to bloom any day now.

Sedum "Autumn Joy"
Sedum "Autumn Joy"

Alchemilla mollis, Lady's Mantle
Alchemilla mollis, Lady's Mantle
As with the Lamb's Ears, I'm experimenting with leaving the old foliage in the hopes it will decay and fertilize the plant.

Aronia arbutifolia "Brilliantissima", Red Chokeberry
Aronia arbutifolia "Brilliantissima", Red Chokeberry

Ajuga genevensis, Geneva Ajuga
Ajuga genevensis, Geneva Ajuga

Agastache foeniculum, Anise Hyssop "Golden Jubilee"
Agastache foeniculum, Anise Hyssop "Golden Jubilee"
Love the coloration on these early leaves. Later, they'll turn bright gold.

Agastache foeniculum, Anise Hyssop "Golden Jubilee" with coccoons
Close up on a bunch of tightly-packed cocoons on the old stems of the Golden Jubilee Agastache.
I've no idea what species spun these cocoons, but perhaps I'll get to see if/when they hatch! 
Anyone have any guesses?

So...how’s spring shaping up in your garden?