The Science Behind the Art™

Articles

Month: November 2016

House Plant Reboot

If your houseplants could talk, they would tell you that they like natural daylight—the kind you get outdoors—better than artificial light of any kind.  They might also say that the winter-time humidity level in your house is too low.  They hope that the compensatory misting you give them does something good for you, because it doesn’t help them very much.  Neither does the overwatering that they get from time to time.  In the midst of saying those things, some of them might yawn, as winter is a time when many houseplants’ growth cycle slows.

What do your plants want in the winter?  The following will help keep them in good shape until spring sets in and growth cycles start anew.

Tidying Up

Anthurium 'A4' (PACORA™) PP11728
Wipe down the leaves of large-leaved plants, such as this Anthurium, if they become dingy or dusty. (Jessie Keith)

Your plants, especially those that have summered outside, probably could use a little TLC.  Prune out weak stems, and cut back those that are too gangly.  If the plant has glossy leaves, like a gardenia, gently wipe the foliage with a damp cloth to eliminate pore-clogging dust.  Check stems, leaves, root ball for pests.  Many can be dislodged with a stream of water or application of insecticidal soap. If the plant is pot bound, repot with fresh media, like Fafard® Professional Potting Mix, in a clean container that is about one third larger than its predecessor.  Winter will not bring much growth, but it won’t bring strangulation either.

Light

Clivia
Clivia are midwinter bloomers that need bright indirect light for good flowering. (Jessie Keith)

If you are blessed with a lighted greenhouse, all you have to do is find appropriate spaces for houseplants that prefer a bit of shade.  But if you, like many gardeners, have to rely on windowsills, try to put most of your plants in south-facing ones.  This may be too much for some popular indoor varieties, like African violets or fancy-leaf begonias.  Save areas with bright indirect light, like north-facing windows for them. Be sure to rotate your houseplants regularly to even out light exposure and avoid lopsided growth.

Fertilizer

In general, fertilize plants when they are in active growth.  For most plants this means little or no feeding in late fall and winter.  The caveat is that you should know your plant.  If it is a winter bloomer, it may need fertilizer during the colder months.  A little research on individual species will ensure that you fertilize properly for winter blooms.

Humidity

Calathea lancifolia
Low humidity caused the leaf edges of this Calathea to turn brown and dry. (Jessie Keith)

Houseplants like more humidity—generally 40-50 percent— than the average indoor environment provides in winter.  If all your plants are in a single room, think about investing in a humidifier.  The added moisture in the air will be good for you, the plants and any wooden furniture in the immediate area.  If a humidifier is not an option, fill deep plant saucers with pebbles and water and stand the plants on them, making sure that the bottoms of the pots are not standing in water.  Replenish the water around the pebbles every few days or as needed.  If plants are grouped together and each stands on a bed of pebbles and water, the humidity level around them will be comfortably high.

Watering

Agave victoriae-reginae 'Variegata'
Succulents, such as this variegated Agave, need very little water in the winter months. (Jessie Keith)

Overwatering is the most frequent cause of houseplant death.  Fortunately, it is also the most preventable.  Before you water, take a look at the plant.  Is the top inch of the soil dry to the touch?  If you pick up the container, does it feel relatively heavy or light?  If the specimen in question is a succulent, it is best to water them very sparingly in winter. If your plant appears to be too dry, gently feel a leaf or two.  Thirsty succulents tend to have slightly flaccid leaves.

If the plant is dry, water thoroughly until water flows out of the holes in the bottom.  Deep watering once or twice a week in the winter is much better for overall health than adding a little water every day. Some houseplants, such as African violets and Streptocarpus, need to be watered from the bottom to keep their leaves from getting wet; moisture on the leaves causes spotting and damage.

Temperature

Pilea cadierei JaKMPM
Tropical plants like this Pilea need warm temperatures to grow well indoors. (Jessie Keith)

The majority of popular houseplants like the same indoor temperatures as the majority of humans. Like us, they also prefer to avoid extremes.  Ambient temperature around 70 degrees F is generally good. If you house your plants on windowsills, don’t let leaves touch the cold glass panes.  Avoid positioning them over radiators too.  Intermittent cold drafts from doors, windows or vents can also be harmful.

Languishing

Kalanchoe blossfeldiana JaKMPM
Flowering potted plants may languish when you first bring them indoors for winter. Give them good care and they should revive. (Jessie Keith)

In late fall or early winter, houseplants that have spent the summer and early fall outdoors often languish while adjusting to lower light, less humidity and fewer daylight hours.  If the plant is in the right light situation and receiving adequate water, it will adapt and recover after a few weeks.  That does not mean that your plumbago or oleander or prize geranium will behave like the blooming fool that it was in the summer.  It means that it will live to dazzle you again when warm weather returns.

The same may hold true with houseplants that you purchase from a nursery, garden center or other retailers.  Many have been raised under near-ideal conditions and will need adjustment time as they get used to your particular indoor environment.
1760FF Pro Potting Mix 2cu RESILIENCE FrontHouseplant care follows the same rules as care of any other kind of plant.  If you are observant, the plant will generally tell you what it needs.  Watch for signals and respond accordingly.  If the soil is too wet, cut back on watering.  If leaves appear burned around the edges, move the plant to a place with less light.  About the time you are feeling droopy due to winter blues, your plants may be similarly afflicted.  If you have given them good care, both you and the plants will recover as the hours of daylight increase.

IMG_2902
Streptocarpus are houseplants that should be watered from the bottom and kept just moist in winter, never wet.

Ornamental Seed Heads for Winter Garden Interest

IMG_5591
The seedheads of Rudbeckia fulgida stay looking pretty into winter and will even hold the snow. (Photo by Jessie Keith)

Winter is the garden’s quiet time when its subtler charms hold sway.  It’s the season of the three B’s – eye-catching bark, colorful berries, and architectural branching – and of evergreen foliage.  And it’s also the time to appreciate the marvelous and often beautiful diversity of seed heads.

Miscanthus sinensis ssp. condensatus 'Cabaret' JaKMPM
Miscanthus sinensis var. condensatus ‘Cabaret’ (Photo by Jessie Keith)

No plants better exemplify this beauty than grasses.  Many produce large, elaborate flower heads that reach their full glory in fall and winter as the seeds ripen and scatter.  Doubtless, the best known of the bunch (at least in eastern North American gardens) is Chinese maiden grass, Miscanthus sinensis.  This variable East Asian native produces huge, plumy, silvery flower heads in late summer on 5- to 8-foot talks that erupt from fountain-like clumps of arching leaves.  The ripening blooms gleam in the slanting fall and winter light, glowing most brightly when backlit by the sun.

Among the many outstanding varieties of Chinese maiden grass are the longtime favorite ‘Gracillimus’ and its descendants, all of which feature narrow leaves with silvery midribs.  Broad, yellow, widely spaced bands mark the leaves of ‘Zebrinus’, which is floppier in habit than the similar ‘Strictus’.  The broad-bladed, variegated Miscanthus sinensis var. condensatus ‘Cabaret’, has cream-striped leaves and reddish plumes that dry to silvery tan in fall.  Compact cultivars such as the 40-inch-tall ‘Adagio’ make a good choice for tighter spaces.  This (and other) grass species may self-sow, particularly in warmer parts of its USDA Zones 5 to 9 hardiness range.

Other notable grasses of winter interest (and of similar hardiness range) include:

The North American native Panicum virgatum (commonly known as switch grass), which produces hazy clouds of dainty pale flowers that darken as they ripen in fall.  Most varieties grow to 4 feet or more.

Cortaderia selloana 'Silver Comet'
Cortaderia selloana ‘Silver Comet’

Fountain grass (Pennisetum alopecuroides), instantly recognizable by its large foxtail-like flower heads on 3-to 4-foot stems above finely textured mounds of narrow leaves.  Several dwarf cultivars (including ‘Little Bunny’) are available.

The upright, tassel-flowered Calamagrostis acutiflorus (feather reed grass), with bronzy blooms that mature to beige tones as they mature in late summer and fall.

Cortaderia selloana (pampas grass) is an imposing tender grass surviving in USDA hardiness zones 8-10. The tall plumes reach 8-12 feet and appear late in the season. It can seed freely, so be cautious where you plant it.

Panicum virgatum 'Prairie Sky' JaKMPM
Panicum virgatum ‘Prairie Sky’ in winter (Image by Jessie Keith)

These and most other ornamental grasses flourish in relatively fertile, not overly dry soil and full sun.  A good nitrogen-rich soil amendment (such as Fafard Garden Manure Blend) will help bring heavy or sandy soils up to snuff.

IMG_5519
Purple coneflower seedheads eventually shatter as their seeds are eaten by birds, but they do offer pleasing winter interest. (Image by Jessie Keith)

Like grasses, many broadleaf perennials have attractive seed heads that make a pleasing sight in winter (particularly when displayed against a blanket of snow).  Among the best perennials for winter interest are species in the aster family that bear persistent conical heads of dark seeds.  The near-black central cones of perennial garden favorite Rudbeckia fulgida remain long after the last golden-yellow petals of its summer-to-fall ray-flowers have dropped.  Usually sold under the name ‘Goldsturm’, it’s one of a tribe of similar ‘black-eyed Susans” from the central and eastern United States.  All are easy-care sun-lovers, are hardy from zones 4 to 10, and have a penchant for self-sowing.  Rudbeckia nitida, by contrast, has greenish cones (with yellow petals) on stately, 4- to 6-foot stems, and is a less enthusiastic self-sower.

Also hailing from prairies and meadows of central and eastern North America are several species of purple coneflower (Echinacea purpurea and others).  The large brown “cones” protrude pleasingly from the snow on 2- to 4-foot stems and also look nice in summer when fringed with purple-pink ray-flowers.  Hybrids and selections of purple coneflower come in a host of flower colors, from white to red to yellow.

IMG_5516
Tall sedums continue to look attractive in the garden well into winter. (Image by Jessie Keith)

The North American prairies are home to several other perennials that make great winter garden ornaments.  The silver-white, spherical flower heads of rattlesnake master (Eryngium yuccifolium) ripen into spiky globes that resemble some sort of miniature medieval weaponry.  They cluster atop 3-foot stems that arise from rosettes of fleshy, spiny, yucca-like leaves.  False indigo (Baptisia australis) and its kin are big bushy legumes that produce blue, white, or yellow pea-flowers in late spring and early summer, followed by peapods that become leathery and brown-black as the seeds mature in fall.  All make wonderful low-maintenance perennials with spring-to-winter interest.

Attractive seedpods are also a feature of the many butterfly weeds (Asclepias spp.) that dot the prairies and fields of eastern and central North America.  The pods split in fall to release seeds that float away on tufts of white down.  Orange-flowered Asclepias tuberosa is one of the best, as is Asclepias purpurascens, which has rose to purple blooms. Tall Sedums (Sedum spp.) of all types also grace the winter with seedheads that can remain attractive through winter.
Garden Manure BlendSweet autumn clematis (Clematis terniflora) is one of the numerous Clematis species (including many shrubby and vining perennials native to central and eastern North America) that bear seeds with plumy, silver-white appendages that continue to draw onlookers long after their flowers have fallen.   Heavy-blooming plants appear to be enveloped with a feathery froth as the seeds (and their plumes) mature.  As with all of the above (as well as the scores of other perennials, shrubs, vines, and trees with ornamental seeds), they’re essential elements of the winter garden and splendid accents for fall and winter flower arrangements.

Evergreen Herbs: Lavender, Sage, Rosemary, and Thyme

Rosemarinus officinalis forefront garden jakMPM 1051
A fall herb garden containing rosemary and lavender (foreground).

Some herbs don’t disappear when winter comes. A suite of favorites from the Mediterranean stay green, keeping our gardens looking pretty and our food tasting good. Designing and cooking with them is easy, but keeping them happy during the winter months requires an understanding of what they need to grow well.
Rather than being herbaceous perennials, meaning they die to the ground in winter and stem from the earth in spring, these herbs are actually shrubs and subshrubs. This means they have woody growth. They require pruning to maintain their good looks and vigorous growth, and if the cold and winter sun becomes too harsh and they are not protected, their stems will die.

Lavender

Lavandula JaKMPM
Lavandula angustifolia is highly attractive to bees.

Valued as a garden and landscape beauty, as well as an aromatic and culinary herb, lavender has both lovely foliage and pretty summer flowers. There are several species that are commonly grown. The most cultivated forms are English lavender (Lavandula angustifolia, 2-3 feet) and French lavender (Lavandula stoechas, 1-3 feet), which are both shrubby perennials with pretty flowers that are highly attractive to bees. The leaves are commonly used are a component of Herbs de Provence, a popular French herb mix used to flavor meats, sauces, and stews.
The common name “English lavender” is actually a misnomer. This evergreen plant originates from the mountain ranges of Spain, France, and Italy where it exists in open, rocky, alkaline soils. When grown in the garden, plants need sharply drained soils and full sun. The whole plant is fragrant. Its summer flowers, may be lavender blue, purple or white, exist in elongated clusters atop long, thin stems. Small, linear, silver-gray leaves densely line the stems. This lavender can survive in zones 5-8, but in the colder end of its hardiness, the stems often experience winter desiccation and damage. Old or unsightly stems should be pruned off in spring after temperatures have begun to warm and new growth appears.

Lavandula stoechas 'Anouk' PP16685 JaKMPM
Lavandula stoechas is tender but offers very pretty plumed flower spikes.

French lavender is a bit more tender than English. It survives in USDA hardiness zones 8-9. It naturally exists on the Mediterranean coasts where conditions are hot and dry. The mounded evergreen subshrub can become quite large with age. It is fully evergreen with fine, toothed leaves of silvery gray-green. In drier weather, the leaves become more linear and silvery. Its slender stems are topped with oval spikes of densely clustered dark purple flowers topped with showy plumes of brighter purple bracts. These appear from late spring through summer.

Sage

Salvia officinalis 'Berrgarden' JaKMPM
Salvia officinalis ‘Berrgarten’ has broad, silvery leaves that always look pretty.

Prized for flavoring Thanksgiving stuffing, sausages, and winter pasta dishes, sage (Salvia officinalis, 2-2.5 feet) is also an attractive, evergreen landscape plant that continues to look nice through winter. It’s broad, dusty gray leaves smell pungent when crushed, and in early summer, stems of pretty violet-blue flowers appear.
Also from the Mediterranean, this sun-loving subshrub requires well-drained soils. It is quite hardy, surviving in USDA hardiness zones 4-8. In colder zones, stems and leaves have a tendency to die back, so spring removal of dead or damaged stems is a must. There are many beautiful cultivars including the broad-leaved ‘Berggarten’ sage and ‘Tricolor’ sage with its purple, cream, and gray-green leaves. All sages have a place both in herb and perennial borders.

Rosemary

Rosemarinus officinalis flower jakMPM 071
Rosmarinus officinalis flowers are pale lavender blue and much loved by bees.

The piney smell of rosemary (Rosmarinus officinalis, 2-6 feet) permeates this sprawling evergreen shrub. Native to the Mediterranean and Caucasus, it grows in rocky sandy soils and can withstand the salt spray of the seashore. It will grow in USDA hardiness zones 7-10, but in colder zones winter stem dieback is common. Some cultivated varieties are hardier than others with the upright cultivar ‘Arp’ surviving to zone 6. Well-drained soils and sites protected from harsh winter weather will help plants make survive the cold. They can also be protected with a winter cover of straw.
Rosemary shrubs can become quite wide and bushy, though low-growing, creeping cultivars also exist. The mat-forming ‘Prostratus’, which sprawls to several feet but only reaches 6-12 inches, is one of these. Pale violet-blue flowers appear along the stems in spring and early summer. Plant rosemary in sharply drained soil and full sun where it will have plenty of room to grow. Where winters are mild, these shrubs can be sheared as topiaries to create an architectural, fragrant border. Harvest leaves and stems to season meats, sauces, and roasted vegetables.

Thyme

Thymus
Thymus pseudolanuginosus is wooly and very low growing.

Creating low mats of minute evergreen foliage, thyme is a garden favorite for herb and rock gardens. It also looks great planted among stepping stones or as a ground cover for the sun. Many species are cultivated and all are culinary, though some taste better than others. French thyme (Thymus vulgaris) is the culinary favorite, with lemon thyme (Thymus citriodorus) following in flavor. The highly prostrate, fuzzy-leaved wooly thyme (Thymus pseudolanuginosus) is very pretty planted along a stone walkway or along a rock wall. The low-growing pink-flowered creeping time is also extra pretty producing masses of pink flowers in spring. Mother-of-thyme (Thymus serpyllum) is a northern European species that also produces masses of pink flowers in spring and makes groundcover. Planting them among sunny, protective rock walls and beds will help protect them through winter and ensure they will continue to look nice.
All of these herbs are mints producing pretty, fragrant flowers that are highly attractive to bees. Their planting needs are similar. All require well-drained soils, and though they can withstand poorer quality soils, they will thrive if their soils are amended with Black Gold® Garden Compost Blend. Plant them in spring, so they will have plenty of time to become established for the cold winter months.
Leaves can be harvested any time of year, which is why sage, rosemary, and thyme are used to flavor winter dishes. Their aromatic flavors offer year-round pleasure and the plants themselves full-season garden interest.

Homemade Pico De Gallo

Fresh Tomato SalsaFeeling a little spicy after you have harvested your fresh veggies?  This pico de gallo recipe tastes delicious with crunchy tortilla chips or as a taco topper.
Ingredients:

  • 2-3 medium fresh tomatoes, diced
  • 1/2 a red onion, finely chopped
  • 1 serrano chili pepper, finely chopped
  • Juice of one lime
  • 1/2 cup cilantro, chopped
  • Salt and pepper (to taste)
  • Cumin (optional)

After dicing and chopping, combine all the ingredients in a medium-sized bowl. Season to taste. If the chili make the pico too hot, add more tomatoes. Wear gloves when preparing chili peppers and don’t touch your eyes. Set aside for one hour in order to for the flavors to blend together. Enjoy!