• Waterwise Gardening | David Salman

Unexpected Hard Frost Predicted

Wow, the forecasted temperatures for tomorrow (Monday) and Tuesday night keep dropping. But if the several inches of snow predicted for Monday materializes, this will be a good thing as snow is an excellent insulator that protects plants during hard-frost events.

Here are a few tips to help protect plants if they need it...

Protecting Recently Transplanted Waterwise Gardening Perennials

For our Waterwise customers, we have been selling a mix of frost-hardened perennials and perennials that have come directly from the greenhouse. Light frosts (28-32°F) will not kill perennials (frost hardened or not) and is not a problem. But temperatures in the low 20’s or teens can be damaging.

If you have not planted your WWG perennials, bring them into the garage or non-freezing space Monday, Tuesday and Wednesday nights. Plant them later in the week or weekend.

If you have planted your perennials;

-many of them have been frost hardened previously (overwintered in our cold frames or cold greenhouse) and will not need protection. It’s easy to identify cold hardened plants as they will just be emerging from the soil in their pots, have purplish colored leaves or are just started to push new leaves from their woody stems.

- Some have not been frost hardened (brought directly from the greenhouse) and can be protected using these methods;

  • Make sure they are well watered.

  • Give some temporary protection like being covered with an upside-down plastic nursery pot (with a rock on top) or plastic garbage bag (anchored around the edges with some rocks to keep from blowing off).

  • Alternately, if you have a large pine tree under which you can gather brown pine needles, mound the pine needles to completely cover the plants. Remove once the danger of frost is past. You can use clean wheat or barley straw in the same way.

If you’re not sure if your individual varieties are cold hardened or not see this attached list.

What About Fruit Trees, Flowering Trees and Other Established Plants?

- This is an unexpectedly hard frost (20°F) that will kill fruit tree flowers; too cold to protect them. Other blooming trees will also lose some if not all of their flowers.

- Established perennials, shrubs and trees will be fine, but might experience a little frost-nip on the tips of the new growth.

-Be sure to disconnect hoses from the faucet to avoid pipe damage.

Temperatures will return to seasonal averages from Wednesday on and new transplants won’t need extra cold protection. Cold weather is an ideal time to plant perennials as they enjoy cool temperatures to establish roots before growing their foliage and flowers.

Frost

hardened Plant Name

yes Achillea fillipendulina Gold Plate (Gold Plate Giant Yarrow)

yes Achillea millifolium 'Red Velvet' (Red Velvet Yarrow)

yes Achillea millifolium 'Sonoma Coast' (Sonoma Coast Yarrow)

yes Achillea Moonshine (Moonshine Yarrow)

yes Achnatherum calamagrostis (Silver Spike Grass)

no Agastache cana 'Rosita' (Rosita TX Hummingbird Mint)

no Agastache cana (Texas Hummingbird Mint)

no Agastache cana (Texas Hummingbird Mint)

no Agastache neomexicana (New Mexico Hyssop)

no Agastache rupestris Grant County, NM (Licorice Mint Hyssop)

no Agastache rupestris Grant County, NM (Licorice Mint Hyssop)

no Agastache urticifolia 'AZ Snow' (FlowerKisser™ Arizona Snow Hummingbird Mint)

no Agastache x 'Ava' (Ava Hummingbird Mint)

no Agastache x 'Blue Boa' (Blue Boa Hummingbird Mint)

no Agastache x 'Blue Fortune' (Blue Fortune Hyssop)

no Agastache x 'Fall Fiesta' (Fall Fiesta Hummingbird Mint)

no Agastache x Desert Sunrise® (Desert Sunrise Hummingbird Mint)

no Agastache x Kudos® Mandarin (Kudo Mandarin Hummingbird Mint)

yes Ajuga reptans 'Catlin's Giant' (Catlin's Giant Ajuga)

yes Ajuga reptans 'Mahogany' (Burgundy Leaf Ajuga)

no Ajuga reptans Blueberry Muffin (Blueberry Muffin Ajuga)

yes Allium x 'Pink Planet' (Hybrid Ornamental Onion)

no Aloinopsis x Psychedelic (Psychedelic Cold Hardy Mesemb)

yes Amsonia jonesii (Jone's Bluestar)

no Anthemis tinctoria 'Susanna Mitchell' (Susanna Mitchell Marguerite Daisy)

yes Aquilegia 'Little Treasure' (Little Treasure Golden Columbine)

yes Aquilegia aff longissima Swallowtail® (Swallowtail Columbine)

yes Aquilegia caerulea (Rocky Mountain Columbine)

yes Aquilegia chrysantha (Goldern Columbine)

yes Aquilegia desertorum (Arizona Columbine)

yes Aquilegia desertorum (Arizona Columbine)

yes Aronia melanocarpa 'Iroquois Beauty' (Iroquois Beauty Chokeberry)

yes Aronia melanocarpa 'Iroquois Beauty' (Iroquois Beauty Chokeberry)

yes Artemisia x 'Powis Castle' (Powis Castle Sage)

yes Aster x frikartii Monch (Monch Hybrid Aster)

no Berlandiera lyrata 'Mora County' (Chocolate Flower)

no Bouteloua gracilis 'Blonde Ambition' (Blonde Ambition Blue Grama Grass) PP#22,048

yes Buddleia alternifolia 'Argentea' (Silver Leaf Spring Blooming Butterfly Bush)

no Bulbine abyssinica (Golden Stars)

yes Calamintha nepetoides 'White Cloud' (White Cloud Calamint)

yes Campanula rotundifolia (Bluebells)

yes Centranthus ruber 'Coccineus' (Red Jupiter's Beard)

yes Cerastium tomentosum (Snow-in-Summer)

yes Ceratostigma plumbaginoides (Hardy Plumbago)

no Cold-hardy Cactus Assortment

yes Coreopsis verticilata 'Zagreb' (Zagreb Threadleaf Tickseed)

no Cotyledon orbiculatus (Red Edged Pig's Ear)

yes Dalea purpurea (Purple Prairie Clover)

yes Dasylirion wheeleri (Sotol)

no Delosperma ashtonii 'Blut' (Blut Cold Hardy Ice Plant)

no Delosperma cooperi (Purple Ice Plant)

no Delosperma nubigenum (Yellow Ice Plant)

no Delosperma Red Mountain® Flame (Red Mountain Flame Ice Plant)

no Delosperma sphalmanthoides (Miniature Ice Plant)

no Delosperma x Delmara® Yellow (Yellow Hybrid Ice Plant)

no Delosperma x Granita® Orange (Granita Orange Ice Plant)

no Delosperma x Granita® Raspberry (Granita Raspberry Ice Plant)

no Delosperma x Jewel of Desert® Garnet (Desert Garnet Dwarf Ice Plant)

no Delosperma x luckhoffii 'Orange Burst' (Orange Burst Dwarf Ice Plant)

no Delosperma x luckhoffii 'Scarlet Burst' (Scarlet Burst Dwarf Ice Plant)

yes Dianthus gratianopolitanus 'Firewitch' (Firewitch Cottage Pink)

yes Echinacea purpurea 'Mellow Yellows' (Mellow Yellows Purple Coneflower)

no Echinacea purpurea 'Ruby Star' (Ruby Star Purple coneflower)

no Echinacea purpurea Pow Wow® Wild Berry (Pow Wow Wild berry Purple Coneflower)

no Echinacea x 'Cheyenne Spirit' (Cheyenne Spirit hybrid Coneflower)

no Echinacea x Sombrero Slasa Red (Sombrero Salsa Red hybrid Coneflower)

no Echinops bannaticus 'Blue Globe' (Blue Glow Globe Thistle)

no Engelmannia peristinia (Engelmann Daisy)

no Eriogonum umbellatum 'Gentle Giant' (Gentle Giant Sulfur Buckwheat)

yes Eriogonum umbellatum 'Poncha Pass' (Poncha Pass Sulfur Buckwheat)

yes Eriogonum umbellatum 'Poncha Pass' (Poncha Pass Sulfur Buckwheat)

yes Eryngium yuccafolium (Rattlesnake Master)

no Eschscholzia californica 'Mikado' (Mikado California Poppy)

yes Festuca glauca 'Boulder Blue' (Boulder Blue Festuca Grass)

no Festuca x 'Siskiyou Blue' (Siskiyou Blue Festuca Grass)

yes Forestiera neomexicana 'Happy Boy' (Happy Boy New Mexico Privet)

yes Forestiera neomexicana Berry Girl (Berry Girl New Mexico Privet)

no Gaillardia grandiflora 'Arizona Sun'

no Gaillardia grandiflora Arizona Apricot (Arizona Apricot Blanket Flower)

no Gaillardia grandiflora Arizona Red Shades (Arizona Red Shades Blanket Flower)

yes Gallium odoratum (Sweet Woodruff)

yes Gaura lindheimeri 'Rosy Jane' (Pink Appleblossom Grass)

no Gaura lindheimeri Intermountain Beauty (Appleblossom Grass)

no Gazania x Butterscotch Baby (Butterscotch Baby African Daisy)

yes Geranium x 'Rozanne' (Rozanne Perennial Geranium) PP#12,175

no Helianthemum nummular 'Belgravia Rose' (Pink Rock Rose)

yes Helianthus maximiliana 'Santa Fe' (Santa Fe Maximilian's Perennial Sunflower)

yes Helichrysum tianshanicum

yes Hesperaloe parviflora Coral Glow (Coral Glow TX Red Yucca) PP29,626

yes Hesperaloe parviflora Coral Glow (Coral Glow TX Red Yucca) PP29,626

yes Hesperaloe parviflora open pollinated (Texas Red Yucca)

yes Hesperaloe parviflora Straight Up Red (Straight Up Red TX Yucca)

yes Hesperaloe parviflora Straight Up Red (Straight Up Red TX Yucca)

no Heuchera bryzoides 'Weston Pink' (Weston Pink Coralbell)

yes Hymenoxys scaposa (Thrift Leaf Perky Sue)

yes Kniphofia x 'Fireglow' (Fireglow Red Hot Poker)

yes Lamium maculatum 'Red Nancy' (Red Nancy Deadnettle)

yes Lamium maculatum 'White Nancy' (White Nancy Deadnettle)

yes Lavandula angustifolia 'Buena Vista' (Twice Blooming English Lavender)

yes Lavandula angustifolia 'Wee One' (Wee One Dwarf English Lavender)

no Lavandula angustifolia 'WWG02' (FlowerKisser® After Midnight English Lavender)

no Lavandula angustifolia 'WWG02' (FlowerKisser® After Midnight English Lavender) 5"

yes Lavandula x intermedia Gros Bleu (Big Blue French Hybrid Lavender)

yes Liatris ligulistylus (meadow blazingstar)

yes Liatris mucronata (Texas Blazing Star)

yes Long Blooming Waterwise Garden I

yes Lonicera reticulata 'Kintzley's Ghost' (Lonicera reticulata 'Kintzley's Ghost')

yes Lonicera sempervirens 'John Clayton' (Yellow Honeysuckly Vine)

yes Lonicera sempervirens 'Major Wheeler' (Major Wheeler Honeysuckle Vine)

yes Lonicera sempervirens Orange (Orange Honeysuckle Vine)

no Mirablis multiflora (Wild Four O'clock)

yes Monarda bradburiana (Eastern Beebalm)

yes Monardella villosa 'Russian River' (Russian River Coyote Mint)

yes Nepeta x 'Junior Walker' (Junior Walker Catmint) #23,074

no Nepeta x Little Trudy® (Little Trudy Dwarf Catmint) PP18,904

yes Oenothera fremontii 'Shimmer' (Shimmer Evening Primrose )

no Oenothera macrocarpa 'Comanche Campfire' (Shimmer Evening Primrose )

yes Oreganum x 'Bristol Cross' (Bristol Cross Ornamental Oregano)

yes Oreganum x 'Erntedank' (Thanksgiving Ornamental Oregano)

yes Origanum libanoticum (Cascading Ornamental Oregano)

no Papaver somniferum 'Lauren's Grape' (Lauren's Grape Beardseed Poppy)

yes Papaver x intermedia (Double Orange Oriental Poppy)

no Paronychia kapela ssp. Serpyllifolia (Nailwort)

no Pelargonium x Black Boar (Black Boar Geranium)

yes Penstemon barbatus Elfin Pink (Elfin Pink Beardtongue)

no Penstemon digitalis 'Dark Towers' (Dark Towers Beardtongue)

yes Penstemon pinifolius 'Compactum' (Compact Pineleaf Beardtongue)

yes Penstemon pinifolius 'Compactum' (Compact Pineleaf Beardtongue)

no Penstemon pinifolius 'Luminous' (Luminous Pineleaf Beardtongue)

yes Penstemon pinifolius 'Magdalena Sunshine' (Magdalena Pineleaf Beardtongue)

no Penstemon pseudospectabilis 'Coconino County'

no Penstemon strictus (Rocky Mountain Beardtongue)

yes Penstemon superbus (Superb Beardtongue)

yes Penstemon x mexicale Pikes Peak Purple® (Pikes Peak Purple Hybrid Beardtongue)

yes Penstemon x mexicale Red Rocks® (Red Rocks Hybrid Beardtongue)

yes Perovskia atriplicifolia 'Blue Spires' (Blue Spires Russian Sage)

no Petunia eximia (Brazilian Red Petunia)

yes Philadelphus microphyllus 'Desert Snow' (Desert Snow Littleleaf Mock Orange)

yes Phlox paniculata 'Jeane' (Jeane Garden Phlox)

yes Pulsatilla vulgaris 'Rosen Glocke'

yes Ribes aureum v aureum (Buffalo Currant)

yes Rosmarinus officinalis 'Madaline Hill' (Madaline Hill Hardy Rosemary)

yes Rosmarinus officinalis 'Alcalde Cold Hardy' (Alcalde Cold Hardy Rosemary)

yes Rosmarinus officinalis 'Santa Fe Dark Blue' (Santa Fe Dark Blue Rosemary)

no Ruschia pulvinaris (Creeping Shrubby Ice Plant)

no Ruschia punctulata (Hantamberg Ice Plant)

no Salvia chamaedryoides (Germander Sage)

no Salvia coccinea 'Jewel Red' (Jewel Red Sage)

no Salvia darcyi (Vermillion Bluffs Mexican Sage)

yes Salvia greggii "WWG03' (FlowerKisser® Coral Pink Sage)

no Salvia microphylla 'Hot Lips' (Hot Lips Littleleaf Sage)

yes Salvia pachyphylla 'Mulberry Flambe' (Mulberry Flambe Mojave Sage)

yes Salvia sylvestris 'Caradonna' (European Meadow Sage)

yes Salvia sylvestris 'May Night' (May Night European Meadow Sage)

no Salvia x 'Burgundy Seduction' (Burgundy Seduction hybrid Sage)

no Salvia x 'Indigo Spires' (Indigo Spires Sage)

yes Salvia x 'WWG01' (FlowerKisser® Dark Shadows Sage)

yes Saponaria ocymoides (Soapwort)

yes Scrophularia macrantha (Red Birds in a Tree)

yes Scutellaria x 'Dark Violet' (Dark Violet Hybrid Skullcap)

yes Scutellaria x 'Dark Violet' (Dark Violet Hybrid Skullcap)

no Sedum spurium 'Red Carpet' (Red Carpet Stonecrop)

no Sempervivum, assorted dwarf cultivars (Dwarf Hens and Chicks)

yes Sporobolus wrightii 'Windbreaker' (Windbreaker Giant Sacaton Grass)

yes Stachys byzantina 'Helen von Stein' (Helen von Stein Lamb's Ear)

no Stachys lavandulifolius (Cottoncandy Lamb's Ear)

no Stomatium species 'Sutherland' (Night Blooming Ice Plant)

yes Tanacetum densum v amani (Partridge Feather)

no Teucrium aroanum (Creeping Silver Germander)

no Thymus praecox v. arcticus 'Coccineus' (Pink Creeping Thyme)

no Thymus pseudolanuginosus (Wooly Creeping Thyme)

no Thymus Reiter (Reiter Thyme)

yes Thymus vulgaris 'Fredo' (Fredo Culinary English Thyme)

no Thymus x 'Pink Chintz' (Pink Chintz Creeping Thyme)

no Verbena peruviana (Red Devil Creeping Verbena)

no Verbena peruviana (Red Devil Creeping Verbena)

no Veronica liwanensis (Turkish Speedwell)

no Veronica oltensis (Thymeleaf Speedwell)

no Veronica x 'Royal Candles' (Royal Candles Speedwell)

no Veronica x Blue Reflection® (Blue Reflection Hybrid Speedwell)

no Viola cornuta 'Bowles Black' (Black Viola)

no Viola tricolor 'Helen Mount' (Johnny Jump Up)

no Viola x 'Yellow Delight' (Yellow Viola)

yes Yucca rostrata (Big Bend Yucca)

yes Yucca schottii (Schott's Yucca)

yes Zauschneria canum v latifolia Sky Island Orange (Sky Island Orange Hummingbird Trumpet)

yes Zauschneria latifolia 'Woody's Peach Surprise' (Woody's Peach Surprise Hummingbird Trumpet)

yes Zaushneria arizonica (Arizona Hummingbird Trumpet)

yes Zinnia grandiflora Golden Eye (Prairie Zinnia)

Waterwise Gardening Plant Guarantee

Our plants are carefully pickedfor you order by our experienced staff. All sales are Final.

Plants are guaranteed to be healthy and strong when leaving our greenhouses. After they leave our care, the plants are your responsibility. Please read and follow our planting instructions for best results.

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