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Taking Houseplants Outdoors in the Spring

Covered porches are a great place to keep plants outdoors through summer.

 

Houses are often stuffy for plants when the weather is mild and pleasant. Most houseplants thrive in the fresh air, natural sunlight light, humidity, and warm temperatures. For these reasons, it’s smart to bring tender houseplants outdoors in the summer months. But, four precautions must be taken before you take them outdoors and bring them back indoors in the fall.

As a preliminary note, I tend to keep my houseplants on my front porch in the late spring, summer, and fall. There are spots with shade and partial sunlight, and I can control the water they get more readily. If you have a covered spot or porch it is the best outdoor spot for your houseplants. I have a houseplant stand to show them off beautifully through summer.

Steps to Taking Plants Outdoors in the Spring

Place indoor plants in an outdoor spot with comparable light after the threat of frost has passed. Tropical plants should not be placed outdoors until nights have become relatively warm.
  1. Make sure the outdoor temperature will stay warm and night frosts are past. I always check the Almanac’s last frost date to determine the last frost date in my area.
  2. Some tropical plants cannot tolerate temperatures below 45-50 degrees. Therefore, it is important to know the temperature needs of your plants. In general, most tropical houseplants like daytime temperatures between 65 and 75°F (15-24°C) and nighttime temperatures between 60-68°F.
  3. Repot plants as needed to make sure they are not rootbound. If they are root stressed during summer, they will be unhappy and require water more often. (Click here to read a good article about repotting houseplants.)

    Rootbound plants should be upgraded/repotted before being taken outdoors for summer.
  4. Feed plants at the start of the season. Choose a fertilizer that’s suited to your plant. Specialty fertilizers include those for orchids, succulents, and tropical foliage plants. Be sure to follow the product instructions. For those gardeners seeking an easy option, try using a quality slow-release fertilizer, such as Proven Winners Continuous Release Plant Food.
  5. Wait to place sun-loving houseplants in the direct sun, and all houseplants should be protected from strong winds until they have become more acclimated to outdoor temperatures. In-home conditions are more regulated than outdoor weather, so plants need time to adjust. After a week or two, most plants will be tougher and better able to withstand the greater extremes of outdoor weather.
  6. Plan to water your plants more often as the days become warmer. Plants subjected to wind and higher temperatures tend to need water more often. Check your plants regularly until you have established a rhythm.
A mix of indoor and outdoor plants will brighten up a front or back porch in the warmer months.

Steps to Taking Plants Indoors in the Fall

Clean and treat plants for any potential pests before bringing them back indoors in the fall.
  1. Once again, check to make sure your plants are not rootbound. If their roots fill the pot, then it is time to repot them in quality potting mix like Fafard Professional Potting Mix. The new pot space will allow plants to grow new roots and take up more fertilizer and moisture when brought indoors.
  2. Place plants in an area with comparable light to reduce stress.

    Look at your plant’s foliage, and make sure they are pest-free before taking them inside. Foliar pests like spider mites, white flies, and aphids eventually cause leaf drop and plant stress, especially indoors. Wash your houseplant’s leaves under the gentle water of the kitchen sink, and spray them with insecticidal soap before bringing them inside. I also recommend removing and replenishing the top two inches of potting soil to catch any pests hanging out in the upper soil layers, such as fungus gnats. (Click here to read a great overview of common houseplant pests.)

  3. Move them to a location with the same light and humidity indoors that they enjoyed outdoors. Try to replicate the outdoor conditions as much as you can. If not possible, the plants may drop a few leaves as they adjust to the transition.
  4. Keep the soil moist, but not too wet. Outdoor plants lose soil water faster due to higher temperatures and wind. Indoors, they generally need less water.

If your houseplants drop a few leaves in transition, don’t worry. Just clean off the dead leaves, give the plants good care, and they should pop back in no time!

Plants often need extra care after being moved from the outside to the inside. They will adjust after a couple of weeks.

 

Garden-Path Fillers: Plants for Cracks and Crevices

Sedums (Sedum spurium shown), thyme, and even a little blue rug juniper act to fill and cover the crevices in this appealing rocky garden path.

Nature abhors bare ground and will happily (and quickly) cover even the smallest bare spaces with weeds.  Keeping those weeds at bay in the cracks and crevices between pavers, stepping stones, or along rock walls can be a perpetual battle. 

It doesn’t have to be that way.

There are plenty of tough, beautiful, neat spreading plants that are small enough to fit into cracks and crevices.  Some have appealing flowers and more than a few sport fragrant foliage. Leaf textures vary from fern-like to fleshy and succulent. 

Depending on the situation, the following plants will beautify those hard-to-fill spaces and end the battle of the crevice weeds.

Soft Greens: Alluring Faux Mosses

Sagina subulata remains pretty and green between these pavers and tolerates foot traffic.

Irish and Scottish mosses (varieties of Sagina subulata and Arenaria verna) are not true mosses at all, but diminutive members of the carnation or Caryophyllaceae family. Thriving in full sun to partial shade, the two moss-like species form mats of thin, creeping stems covered with soft, tiny leaves in green (most often in Irish moss) or golden-green (most often in Scotch moss). In spring, Sagina varieties are adorned with single white flowers, while Arenaria bear their blooms in clusters. Rising to a height of only about one inch tall, the plants tolerate light foot traffic and are generally hardy in USDA Plant Hardiness Zones 4-8.

Thyme for Fragrance

Thyme is a very effective evergreen stone crevice filler that bears spring flowers and season-long fragrance.

Some avid gardeners make entire lawns of fragrant thyme species and varieties, but the plants are also great crevice fillers. Many will do the job, but all like excellent drainage and full sunshine. Among the most popular are elfin thyme (Thymus serpyllum) and mother-of-thyme (Thymus praecox), which share other nicknames that include creeping thyme, wild thyme, and others. The European natives belong to the mint, or Lamiaceae family and are related to common culinary thyme (Thymus vulgaris) and are equally edible. Growing only about 1/4 inch tall and spreading up to one foot, each plant features scores of tiny, ovoid leaves, with the characteristic thyme fragrance. 

The flowers, appearing in June or July, are deep pink in Thymus serpylluum and somewhat lighter in Thymus praecox. Thriving in USDA Zones 4 or 5-8, the perennial plants will attract butterflies and pollinators, but not deer, and will withstand foot traffic. In mild climates, thymes are evergreen.

Creeping Speedwells

Turkish speedwell (Veronica liwanensis) becomes covered with violet-blue flowers in spring.

Though not real thyme, thyme-leaf speedwell (Veronica oltensis) shares thyme’s ground-covering nature. The tiny leaves of these snapdragon relatives are evergreen on plants that rise to only 1 inch in height.  Thyme-leaf speedwell’s crowning glory is the tiny blue flowers that cover the plants in spring. Blooming and spreading best in full sun and flourishing in zones 4-9, the plants can withstand low water conditions once they are established. Equally drought-tolerant Turkish speedwell (Veronica liwanensis) is another great solution for cracks between bricks or pavers. The characteristically tiny leaves are glossy green and the plants are quick to establish because the stems root as they travel.  Periwinkle-blue flowers appear in late spring on plants that grow 1 to 2 inches tall and are hardy in zones 3-9.

For something different and cheerful, little Veronica repens, or creeping veronica, is perfect. The foliage is dense and golden on plants that grow 1 to 2 inches tall. Creeping veronica is evergreen in southern gardens and thrives in zones 4-8.

Steppable Sedums

Creeping sedums of all types grow beautifully in crevices. Evergreen forms are most desirable for their year-long coverage.

Always in vogue, some succulent sedums also make excellent crevice-fillers. One terrific choice for larger cracks or spaces is Caucasian stonecrop (Sedum spurium), also known as two-row stonecrop, which grows to about 3 inches tall, with a spread of up to 18 inches. Its leaves are deciduous, but dense roots hold soil between cracks through winter. The fleshy leaves of the popular and somewhat less vigorous ‘Tricolor’ variety are green-tinged with pink, turning red later in the season. Tiny pink flowers add interest in late spring to early summer. The evergreen gray sedum (Sedum pachyclados) is similar in size and spread to Caucasian stonecrop, with miniature blue-green “hen and chick” type leaf rosettes that support pink flowers in mid to late summer. These sedums like relatively dry, well-drained soil as well as lots of sunshine and grow best in zones 4-9.

Other Great Creepers

New Zealand brass buttons looks ferny and spreads nicely between pavers or in gardens.

Creeping mazus (Mazus reptans) is another great perennial creeper, native to the Himalayas and hardy in USDA zones 5-8.  The narrow green leaves stay vibrant into the fall, but the tubular, blue-purple, and white flowers are what set the two-inch-tall grower apart. With its love of damp soil, creeping mazus is perfect for low or wet cracks or crevices 

The fancifully named New Zealand brass buttons (Leptinella squalida) is a creeper that features leaves that look like tiny ferns.  The “brass buttons” of the common name refer to the small yellow flowers that bloom in June or July, but the foliage plays the real starring role for this sun-loving species. ‘Platt’s Black’ is a striking variety with near-black leaves. Flourishing in USDA zones 4-10, New Zealand brass buttons spreads readily by underground rhizomes.

Low Maintenance for Low Growers

There are lots more creepers to consider for the garden, so ask your local garden center specialist for the best creepers for your area.

Once creepers and crevice fillers are established, they generally do not take much maintenance. If soil is lacking in the planting spaces, fill in with a quality product like Fafard Premium Topsoil. Water regularly until the plants are established. The best time to sheer back crack and crevice fillers is right after they bloom. At other times, trim to maintain size and shape. parameters.

Black Plants for Goth Gardens

Black Plants for Goth Gardens Featured Image

What better way to celebrate the Halloween season than to design and plant a Goth Garden? Admit it: you need one.

Of course, you’ll also need plants that look the part. Spiky or bizarrely shaped or ghostly hued plants are obviously essential (a contorted beech – Fagus sylvatica ‘Tortuosa’ – would fit to a twisted tee). Most of all, though, you’ll want some black flowers – or as close to black as you can get. The possibilities are surprisingly many.

Molly Sanderson Viola (Viola ‘Molly Sanderson’, Zones 5-10)

Black pansies
Black pansies look the part in cool fall plantings and may even survive through winter.

Plum-black miniature pansies envelop this winsome – but slightly spooky – little perennial in spring, and again after the return of cool weather in fall. Each flower flashes a sunny-yellow eye, accenting and enhancing the surrounding blackness. The blooms are darkly adorable in combination with ‘Jack Be Little’ mini-pumpkins. Available as plants or seed, ‘Molly’ is a short-lived perennial that often persists by sowing itself about. It’s longest-lived (and evergreen) in areas with mild summers and moderate winters.

Black Sprite Mountain Knapweed (Centaurea montana ‘Black Sprite’, Zones 3-9)

The spidery purplish-black flowers of 'Black Sprite' in summer
The spidery purplish-black flowers of ‘Black Sprite’ appear in summer.

Spidery-petaled midnight-purple flowers open from cobwebbed buds in late spring and early summer over contrasting clumps of gray-green leaves. At 18 inches tall, the flower stems are somewhat shorter than those of standard-issue violet-blue-flowered Centaurea montana. Cut them black after bloom, and you’ll be rewarded with a second round of sinister flowers in summer. As with ‘Molly Sanderson’, this sun-loving, relatively short-lived perennial usually stays in the garden via self-sown seedlings.

Chocolate Cosmos (Cosmos atrosanguineus, Zones 7-10)

Dark-chocolate colored cosmos flowers
The dark-chocolate colored flowers of this cosmos are fragrant and summer blooming.

This Mexican native earns its common name not from the black-maroon color of its daisy-shaped summer flowers, but from their delicious chocolate-laced fragrance. Appearing on 2-foot stems in summer, the flowers are at their most prolific in sunny sites with fertile well-drained soil (amend overly heavy soils with Fafard Premium Natural & Organic Compost). In colder regions, lift the frost-tender, tuberous roots before the ground freezes in fall, and overwinter them in open paper bags in a well-aerated location. Plants will winter in the ground into USDA Hardiness Zone 7 if heavily mulched with pine needles or straw in early winter.

Voodoo Lily (Sauromatum venosum, Zones 6-10)

Dragon arum
Dragon arum has a striking black flower.

An altogether different sort of fragrance wafts from the gratifyingly grotesque spring “blooms” of voodoo lily. Standing 2 feet tall, each inflorescence comprises a central sooty-purple truncheon (the “spadix”), cowled by a lime-green, black-mottled “spathe”. Their macabre coloration – and fetid scent – is a clarion call to carrion-feeding insects. Huge horseshoe-shaped compound leaves with fanned lance-shaped leaflets push up from the underground tubers after the flowers collapse. Famed plantsman Graham Stuart Thomas aptly described this as the flower Beelzebub would present to his mother-in-law. Or he might have been referring instead to dragon arum (Dracunculus vulgaris), another dark member of the arum family that is similarly bizarre and slightly more cold-tender (USDA Zone 7 rather than Zone 6). Both are must-have plants for partly shaded Goth gardens. Plant the tubers in early spring.

Black Widow (Geranium phaeum, Zones 4-9)

'Samobor' flowers
Near-black flowers make the early summer bloomer ‘Samobor’ uniquely beautiful.

Given the name – and the shadowy deep-purple flowers with back-swept petals that nod ruefully from 2-foot stems in late spring and early summer – this is another must-have. The relatively large, lobed, maple-shaped leaves form an attractive foil for the flowers. Look for ‘Raven’, which has especially dark-hued blooms, and ‘Samobor’, whose leaves are generously marked with dark purple splotches that echo the flowers. All forms are tough perennials that tolerate shade and drought and are hardy to USDA Zone 4.

Black Lenten Rose (Helleborus x hybridus (black varieties, Zones 4-9)

Black hellebores
Black hellebores look very striking in the late-winter landscape. (Image by Kenpei)

Indispensable shade perennials that bear saucer-shaped blooms in late winter and early spring, the swarm of hybrids known collectively as Lenten roses come in numerous near-black forms. They’re also prized for their verdant, hand-shaped, evergreen leaves, which sometimes are splashed with silver. Many of the blackest varieties – including ‘Black Diamond’, and the double ‘Dark and Handsome’ – can be purchased as seed or plants, and vary slightly in flower color. Give them partial shade, humus-rich soil, and a top-dressing of Fafard Compost for optimum performance.

Persian Lily (Fritillaria persica, Zones 5-8)

Blackish bells
Tall spikes of blackish bells make this arguably the most striking flower of the bunch.

In mid-spring the large, skunky-scented bulbs of this Central Asian native send up 30-inch spikes of nodding chocolate-purple bells dusted with a silvery bloom. The cultivars ‘Adiyaman’ and ‘Senköy’ are especially dark-hued. Persian lily is excellent for combined with “black” tulips such as ‘Queen of the Night’ and ‘Black Parrot’. All the above appreciate full sun and fertile well-drained soil.

Fall is the best time to plant not only Persian lily but also most of the other black-flowered beauties described above. Get them in the ground now – amending with Fafard compost and topsoil as required – to get your Goth Garden off to a great start!