Posts by Denny Schrock

Denny Schrock

frosted

It isn’t pretty. Three successive nights of freezing temperatures in my yard have taken their toll on a landscape far advanced beyond its normal stage of growth for this time of year due to an unseasonably warm March. At first glance things don’t look too bad. The creeping phloxes are still blooming their hearts out; the Bloomerang lilac sports its fragrant blossoms next to the deck; and the overall effect is one of a lush, green landscape. But look a little closer, and you can see the damage.

I expected some injury to plants. With several thousand different perennials, trees and shrubs in my half-acre yard, I simply couldn’t protect them all. With the exception of tender annuals and tropicals that I covered with floating row covers, moved into the garage or crowded onto the front porch and deck, everything else had to fend for itself through the freezing weather. I’m unsure of the exact low temperatures the past three nights. However, a nearby weather station reported 28 degrees F the first night, and it was supposedly a few degrees colder the second night. This morning the yard was covered in white once again.

This is what 'Jane' magnolia looked like a couple of weeks ago.

Some of the plants showing frost damage were predictable. Saucer magnolias often get nipped by late frosts here in the Midwest. True to form, ‘Jane’ magnolia was injured in this freeze cycle. But because she was already done blooming, it was her leaves that turned brown and limp rather than her gorgeous pink blooms. Leaves of butterfly bushes and caryopteris often curl with the first frost of fall; they did so this spring too.

Other injured plants were more surprising. Chrysanthemums withstand fall frosts with ease, blooming through early autumn cold snaps. But their tender new shoots in spring are quite sensitive to the cold. In some instances, damage may be due to microclimates in the yard. My ‘Miss Canada’ Preston lilac was totally trashed (see photo below), while all other lilacs escaped unscathed. Of the dozen or so daylilies in the yard only one showed injury. ‘Strawberry Candy’ developed bleached leaves where frost settled on top of the plant.

This pink flowering deutzia was fully budded with bright green foliage just three days ago.

I'm sure that this 'Miss Canada' lilac won't be blooming this year!

Although the leaves are still green, this ginkgo foliage looks more like wilted lettuce after the freeze.

Kamtschatka sedum shows the effects of microclimate. The green side of the plant was next to some ornamental grass which protected it.

Although the shepherd's crook on these peonies looks bad, they fully recovered, and now are standing fully upright.

I conducted an inventory of damaged plants, dividing them into “severely damaged” and “lightly damaged” categories. Severely damaged plants showed extensive wilting, browning and/or dieback. Lightly damaged plants included those that had a few wilted shoots, nipped leaf tips or slight discoloration. Of course, these are somewhat arbitrary divisions, but I’m including the lists here for you to compare damage in your yard or to help you know which plants are most sensitive, and need protection the next time freezes arrive.

Severely Damaged:
‘Jane’ magnolia – sweetbay magnolia was OK
Blue mist spirea (Caryopteris) – all varieties in the yard
Deutzia – ‘Chardonnay Pearls’ and ‘Pink’, virtually all foliage blackened
‘Miss Canada’ Preston lilac (Syringa) – all other lilacs undamaged
Ginkgo (Ginkgo biloba)
Butterfly bush (Buddleja) – all varieties
Endless Summer hydrangea – other mopheads also affected; paniculata types except Little Lime unaffected
Astilbe – all varieties
Hardy kiwi (Actinidia)
Chrysanthemum – half a dozen varieties burned back
Kamtschatka sedum (Sedum kamtschaticum) – a dozen other sedum species and varieties mostly unaffected
Japanese anemone – all leaves blackened
Rose of Sharon (Hibiscus syriacus)
Strawberry – open blossoms blackened; foliage unscathed
Purple flamegrass (Miscanthus purpurascens) – almost all new shoots browned
Russian sage (Perovskia) – all shoots wilted and drooping

Lightly Damaged:
Lemon balm – a few brown leaves
St. Johnswort (Hypericum) – shrubby kinds OK; herbaceous types show some wilting
Jupiter’s beard (Centranthus) – a few damaged leaves
Boxwood (Buxus) – only one variety out of four had wilted stem tips
Weigela – only one variety affected the fist night; several more damaged the second night
Mukdenia – outer leaves browned
Lungwort (Pulmonaria) – some damaged leaves
Calamint (Calamintha) – half of shoots affected
Crape myrtle (Lagerstroemia) – only a few new shoots damaged
Lily (Lilium) – one or two varieties of the dozen in the yard showed watersoaked leaves
Rose (Rosa) – Pink Double Knock Out and Deja Blue had wilted new shoots; more than a dozen other types OK
‘Purple Pygmy’ agastache – half a dozen other agastaches had no damage
Itoh peony – a few bronzed and wilted leaves
Beautyberry (Callicarpa) – a few new shoot nipped
Japanese painted fern (Athyrium) – some browned leaves
‘Sarastro’ campanula – half a dozen other campanulas were fine; this one was wilted
Dwarf goatsbeard (Aruncus) – browned foliage
Japanese toad lily (Tricyrtis) – watersoaked foliage
Leadwort (Ceratostigma) – some browned foliage
Lavender (Lavandula) – one variety with wilted tips; half a dozen others OK
‘Rozanne’ geranium – a few wilted stems
‘Strawberry Candy’ daylily (Hemerocallis) – bleached foliage
Winterberry holly (Ilex) – new growth browned; also some damage to blue holly
Chinese cabbage – some bleached leaves; they had been transplanted outdoors just a week earlier

 


Denny Schrock

first salad

A blend of lettuces dressed with crumbled blue cheese and croutons is a springtime dinner treat.

Salad season has arrived. I devoured the first salad from the garden last night for dinner. This first batch of salad greens came from various lettuces, spinach, and corn salad that overwintered in the garden with no protection, a first-time occurrence in my Des Moines garden.

I could have harvested them earlier, but I’ve been traveling so much lately that I’ve not had the opportunity to do so. The outlook for more springtime salads from the garden looks rosy. The early-March planting of lettuce and spinach is almost ready to reap as well. I should thin them and use the rejects as gourmet baby greens.

Radishes from the garden are also ready to pick. These first red orbs are sweet and mild because they have matured quickly in the pleasant spring weather. Now if my tomatoes would just ripen in the next two weeks…….!

Fingernail-sized radishes will add color to spring salads.

Recently seeded rows of lettuce and spinach are ready to thin and use in salads.


Denny Schrock

springtime in the Ozarks

Spring break for me this year was a week-long road trip through the Ozarks. In addition to visits with family and friends at Long Creek Herbs in southern Missouri, friends in Fayetteville, AR, and a side trip to the Clinton Library in Little Rock, public gardens were part of my must-see agenda. The timing was perfect. An unseasonably warm spring had coaxed redbuds and flowering dogwoods, into bloom, covering the hillsides with splashes of color. In town, lilacs, spireas, and spring bulbs were displaying their finery.

Eureka Springs, AR is a unique historical town with winding streets perched on hillsides. Nearly a dozen springs bubble up from the rocky outcroppings, and the town has turned the areas around each into pocket parks. The display of violas and painted twigs below, was at one of these mini-parks located, appropriately enough, on Spring Street.

Compton Gardens in Bentonville, AR features native plants of the Ozarks. This is the former estate of Dr. Neil Compton, who was instrumental in saving the Buffalo River as part of the National Park Service. Walkways through the grounds guide visitors to displays of groomed native plants. The trail system also connects to Crystal Bridges, the fantastic new museum of American art.

Golden ragwort (Senecio aureus) is a native wildflower with yellow daisylike blooms in spring.

Carolina silverbell (Halesia tetraptera) is a native tree with springtime blooms that resemble dangling white bells.

The Botanical Garden of the Ozarks is a relatively new public garden, but it has a lot to offer including a children’s garden, butterfly house, rock garden, water garden, native garden, sensory garden, vegetable garden, and Japanese garden. Despite constant rain during my visit, I was able to snap a few photos, including a planted concrete chair, obviously not intended for seating.

Hens and chicks cover the seat cushion on this whimsical "chair" next to the children's garden at the Botanical Garden of the Ozarks.

This Euphorbia martinii Ascot Rainbow was in full bloom at the Botanical Garden of the Ozarks.

 


Denny Schrock

early spring flowering shrubs

Flashy golden forsythias and splashy pink saucer magnolia take center stage in many early spring landscapes. But these leading ladies aren’t the only shrubs that can make an impact in your yard at this time of year. Many other woody plants are worthwhile additions for their vernal display of showy blooms. If you’re looking for something a little more unique, consider one of the beauties shown below.

Hybrid witch hazel (Hamemelis X intermedia) kicks off the spring season with its straplike gold or copper petals, usually blooming in February.

White forsythia (Abeliophyllum distichum roseum), also called Korean abelialeaf, is neither a forsythia nor an abelia, although it has qualities resembling those shrubs. It precedes the yellow blooms of true forsythia by a week or more.

Double Take 'Pink Storm' flowering quince (Chaenomeles Double Take 'Pink Storm') bears clusters of rosy pink blooms backed by glossy clear green foliage.

Flowering almond (Prunus glandulosa 'Rosea Plena') grows just 4 feet tall and in spring is covered with fully double pink blooms.

Regent serviceberry (Amelanchier alnifolia 'Regent') is a season-long beauty. The white spring flowers are followed by tasty purple-blue fruits, and the leaves turn gold, orange, and red in fall.


Denny Schrock

Crocus plus

After a couple of days with record warmth in the 70s and 80s, early spring bulbs are displaying their vernal glory in my yard. As of March 14 the landscape features eight different types of crocuses, three iris varieties, three kinds of daffodils, spring meadow saffron, snowdrops, winter aconite, and pasque flower in bloom. This early color may not last long because temperatures are predicted to remain in the 70s through next week, but it’s such a welcome sight to see splashes of color dotting the yard before winter officially makes its exit.

Here are some current photos from the yard.

My favorite crocus is Crocus fuscotinctus. Its bright gold flowers have purplish maroon stripes on the outside of the petals, and it's always one of the first to come into bloom. It's growing near the mailbox, where it withstands winter road salt.

It's easy to see where the tricolor part of the name comes from for Crocus sieberi 'Tricolor'. Lilac-purple petals have a golden base with a stripe of white in between.

Crocus vernus 'Grand Maitre' translates as Grand Master, an apt name for this gorgeous purple crocus with an intricately frilly orange stigma.

Crocus flavus has large, intense yellow blooms that open wide only when the sun is shining. On cloudy days and at night, they close up.

Spring meadow saffron (Bulbocodium vernum) is a crocus cousin native to the Pyrenees and Alps. It is sometimes called Colchicum vernum.

Spanish iris (Iris hispanica 'George') has deep purple blooms with colorful markings on its nearly tubular falls. It grows nearly one foot tall.

Reticulate iris (Iris reticulata 'Harmony') has purple-blue petals with distinctive markings on its falls. It reaches just six inches tall.


Denny Schrock

Ladies and gentlemen, start your onions!

Gardening with vegetables and annual flowers is a race against time and the elements. If you jump the gun, spring frost may knock back tender seedlings. If you delay too long, yields may be reduced because plants won’t fully mature before fall freezes arrive or the excessive heat of summer stymies growth. Onions are an example of a plant sensitive to day length. Varieties adapted to the northern U.S. form biggest bulbs during the long days of June and July. Delayed planting results in decreased bulb size because they form during the shorter days of late summer.

In response to this year’s mild winter, I’m betting on an early spring. I seeded onions in the greenhouse in mid-January. The seedlings are up and growing strong, and will soon be ready to transplant into the garden. If you haven’t started onion seeds yet, you can still direct seed them in the garden, purchase transplants from a garden center, or plant onion sets.

Seedlings of onion and annual flowers grow quickly in a large box with a seedling heat mat to provide bottom heat.

This weekend I’ll be starting dozens more vegetables and annual flowers in the greenhouse seed-starting chamber. When seed orders arrive, I file away seed packets by planned start date, storing them in the extra refrigerator in the garage to prolong their viability.

Store garden seeds in air-tight containers in the refrigerator to keep them fresh longer.

I did a quick inventory of seed packets to start on March 1, and came up with the following list of things that I’ll be planting this weekend.
Flowers:
Salvia ‘Summer Jewel Pink’ (an All-America Selections winner for 2012) and ‘Blue Victoria’;
Dianthus ‘Parfait Raspberry’;
Celosia ‘New Look Red’;
Gomphrena ‘Dwarf Buddy’ and ‘Qis Purple’;
Baby’s breath ‘Gypsy Deep Rose’;
Lavatera ‘Hot Pink’;
Marigold ‘Hero Bee’;
Snapdragon ‘Twinny Rose Shades’;
Lobelia ‘Crystal Palace’

Vegetables:
Tomato ‘Lizzano’, ‘Terenzo’ (AAS winners for 2011), ‘German Johnson’, ‘Mortgage Lifter’, ‘Pruden’s Purple’, ‘and ‘Pompeii’;
Pepper ‘Black Olive’, ‘Cayenetta’ (AAS winners for 2012), ‘Odessa Market’, ‘Corno di Toro Giallo’, ‘California Wonder’, ‘Gordo’, ‘Premio’;
Eggplant ‘Black Beauty’;
Basil ‘Queenette’ and ‘Mrs. Burn’s Lemon’;
Broccoli ‘Liberty’, ‘All Season’s Blend’, and ‘Romanesco’;
Cauliflower ‘Grafitti’;
Chinese cabbage ‘Little Jade’ and Michihli’;
Lettuce ‘Garden Babies Butterhead’;
Beet ‘Bull’s Blood’

I’ll wait several weeks to start quick-growing heat lovers such as zinnias, squash, and ornamental cotton. By then, I’ll move frost-hardy annuals to the covered deck or front porch to acclimate to outdoor growing conditions. They’ll grow slower there than in the greenhouse, but as the adage goes, “slow and steady wins the race”.