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Growing Perfect Garden Peonies

‘Coral Charm’ has beautiful peachy coral flowers. (Image by Jessie Keith)

It’s time to plant peonies! Nothing says spring like a garden full of bright, beautiful peonies (Paeonia spp.). Their big, fragrant flowers are great for cutting and come in shades of red, pink, white and yellow and may be single, semi-double, or double. The plants themselves are resilient and can live as long as 100 years or more. This is why established clumps of these old-fashioned garden flowers often exist around old homes.

First cultivated in China, where an estimated 41% or the world’s species reside, peonies have been the object of adoration for nearly 4000 years. There are hundreds of variable woody and herbaceous varieties for the garden. All are long-lived and wonderfully beautiful in their own right.

Herbaceous Peonies

Paeonia lactiflora 'Sarah Bernhardt' JaKMPM
Double-flowered varieties like ‘Sarah Bernhardt’ should be staked to keep their flowers from flopping. (Image by Jessie Keith)

Common garden peonies (Paeonia lactiflora) are the classic herbaceous peonies found in American gardens. The large, bushy plants produce loads of big, late-spring flowers that are hardy to USDA Hardiness Zones 3-8. Caging or staking is recommended for double-flowered varieties because weak stems often cause the flowers to flop to the ground in heavy rains. Through summer, these perennials are not very attractive, so it’s best to plant other pretty garden flowers around them for continued seasonal interest. In winter, herbaceous peonies die all the way to the ground and old stems should be cut back.

Paeonia lactiflora 'Gold Rush' JaKMPM
‘Gold Rush’ is a classic Japanese-type peony. (Photo by Jessie Keith)

Herbaceous peonies have many flower forms other than standard single, semi-double, and double types. Bomb peony flowers have a big round puff or “bomb” of petals, and Japanese- and anemone-peony flowers have golden puffs of color at the center of the blooms.

Exceptional varieties include the single, clear-pink-flowered ‘Pink Dawn’, the classic pale double pink ‘Sarah Bernhardt’, the semi-double, peachy coral ‘Coral Charm’, and the white and pale yellow, Japanese-flowered ‘Gold Rush’.

Tree Peonies

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Double, red-flowered tree peonies in full bloom. (Image by Jesse)

The spare, shrubby habits of tree peonies don’t impress, but the spectacular flowers they produce are some of the biggest and best around. Blooms can reach up to 10” across and come in shades of white, pink, and purplish red as well as burnished yellows and corals. Flowers burst forth from late spring to early summer for a period of around two weeks. Grow them in full sun to partial shade.

Plants are slower growing than herbaceous peonies, and their branches can be brittle, so it is important to protect them from the wind. Even though most are hardy to USDA Hardiness Zone 4, their buds can be damaged by frost—another reason to plant them in a protected spot.

Great varieties include the American Peony Society Gold Medal Winner ‘Age of Gold’, which has huge golden blooms—often with more than one flower per stem—and reaches 5 feet in height. The semi-double, pink-flowered ‘Hana Kisoi’ is another garden classic that blooms in May and originates from Japan. The brilliant white-flowered ‘Phoenix White’ bears enormous single flowers, grows relatively quickly and will add sparkle to partially shaded gardens.

Intersectional Hybrid Peonies

Paeonia 'America' JaKMPM
‘America’ is a wonderful magenta-red intersectional peony. (Image by Jessie Keith)

Intersectional (Itoh) peonies are crosses between tree and herbaceous peonies, and they offer the best characteristics of both. Their big flowers tend to be more like those of tree peonies, but they have herbaceous habits. They bloom in late spring and have stronger stems than standard herbaceous peonies, so staking is not needed.

Itoh peonies were first bred in Japan in the 1960s. Since then lots of stellar varieties have come to the market. Choice varieties include the single, magenta-red ‘America’, the semi-double lemonade colored ‘Bartzella’, and the award-winning ‘Garden Treasure’, which has semi-double flowers of palest tangerine.

Growing Peonies

All peonies flower best in full, bright sunlight, though tree peonies can take partial shade. Tree peonies should be protected from strong winds and harsh winter exposure, and double-flowered herbaceous peonies must be staked or caged if you want to keep their flowers off of the ground.

Plant new peonies in early spring or fall. Rich garden soil with a neutral pH is best. Soil that is too acid or too alkaline can cause nutrient deficiencies and result in leaf chlorosis (yellowing between the leaf veins). Before planting new peonies, amend the garden soil with fortifying Black Gold Garden Soil. Established peonies can be mulched in spring with Black Gold Garden Compost Blend. Plant the roots just below the soil surface. If you plant them too deeply, this can inhibit flowering. Small peony starts may take a year or two before reaching full bloom. Feeding peonies in early spring will support flowering and foliage health.

Large herbaceous peony clumps can be divided in fall. Just be sure to dig the large, fleshy roots deeply, and gently cut new divisions from the parent plant. Mulch new plantings lightly and water them well.

Globe-shaped peony buds attract ants, but the insects won’t damage the flowers. They simply feed on the sweet juices surrounding the unopened petals. Before cutting the flowers for indoor arrangements, just be sure to brush off any lingering ants.

When peonies are in full bloom, they look so impressive! And, you can be sure that they will remain in your garden for years to come, offering lots of sweet-smelling blooms for cutting and enjoyment.

The pink peony 'Monsieur Jules Elie' has bomb-type flowers. (Image by Jessie Keith)
The pink herbaceous peony ‘Monsieur Jules Elie’ has bomb-type flowers. (Image by Jessie Keith)

Mike Darcy’s Favorite Fall Trees and Flowers

This Stewartia pseudocamellia is in fall color.

The fall season is upon us and what a glorious time of year it is. As I walk around my neighborhood and drive around Portland, the many deciduous trees are turning brilliant shades of color. The more brilliant they are, the better.

Favorite Fall Trees

Stewartia pseudocamellia seed pods, L Foltz 2014
Stewartia pseudocamellia seed pods

Many maples are turning red, some are orange, and others are shades of yellow.  The Ginkgo (Ginkgo biloba) trees are turning golden yellow, and our summer annuals are telling us that their time is almost over.  Sometimes we can have a tree that gives us scarlet fall foliage as well as beautiful seed pods.  Stewartia pseudocamellia is just such a tree. Mine is planted in my front yard where it takes center stage.

 

Salvias

Salvia splendens Saucy™ Red
Salvia splendens Saucy™ Red looks great well into fall.

Yet, there is still much color in the garden, not only from foliage but from flowers as well.  In my own garden, I am quite a Salvia fan and always willing to try new varieties.  This past spring I purchased Salvia splendens Saucy™ Red, and I was rather disappointed with it in summer.  It did not flower well compared to my Salvia guaranitica ‘Black & Blue’.  Well, I had a very pleasant surprise this September. Evidently, Saucy™ Red likes cooler weather, shorter day-length, or maybe both, because it burst into full bloom and has continued ever since.  It is mid-October, and the 7-foot-tall plant has burnished scarlet flowers on almost every stem. Sadly, the tender plants are only hardy to USDA Zones 9-10, so I will have to replant if I want to enjoy this Salvia again.

Impatiens tinctoria

Impatiens tinctoria
Impatiens tinctoria is an unusual garden flower that looks great in fall.

Another new garden flower this year is the 8-foot-tall, large-flowered, Impatiens tinctoria, which comes from the rain forests of East Africa.  I had first seen it growing in a friend’s garden three years ago and was surprised to learn that it is a winter hardy perennial, surviving USDA Zones 7-11.  This is my second year to grow it, and I learned that it likes grows best in shade with protection from the hot afternoon sun. In the spring, I worked lots of humus into the soil around it and mixed in Black Gold Natural & Organic Potting Soil. Today my plants are over 6 feet tall and blooming with a flower that does not look anything like a garden impatiens.  These flowers are fragrant at night and attract much attention from garden visitors.

Cover Crops

Now is the time of year to put the summer vegetable garden to bed.  The tomatoes are finished, as well as the beans, squash, peppers, etc.  Once these plants are removed, it is an ideal time to prepare the soil for next season.  Mix Black Gold® Garden Soil 0.05 – 0.02 -0.05 into the beds and plant a cover crop. Cover crops are broadcast legumes, or grasses such as buckwheat, that are planted to cover the garden in winter and are tilled under in spring.

BG_GRDNSOIL_1CF-FRONTLegumes are plants in the Pea Family (Fabaceae) and include clovers and vetches. With the help of symbiotic bacteria called Rhizobium, they “fix” nitrogen from the air back into the soil, making it available to other plants.  Thus, by planting a cover crop, you increase the nitrogen level of your soil while also protecting your beds from erosion and aggressive winter weeds. The added organic matter from the spring-tilled cover crop with also benefit your garden soil.

We always get some “sunny windows” during this season.  These windows give us a wonderful opportunity to get out in the garden and do fall chores.  Fall is also a great time to “edit” your garden.  We all have plants that have gotten too big, are in the wrong place, or maybe we are tired of them.  Walk around your garden with a note pad and make notes on garden editing that you can do throughout winter.  But, most importantly, enjoy the season and its many colors.

Late-Summer Gardening in the Pacific Northwest

Fuchsia ‘Dying Embers’ has lovely deep purple flowers that draw hummingbirds.

It seems as though the gardening season has flown by, and here it is August already.  I think August is a good month to relax and enjoy the fruits of your labor; summer is not quite over and autumn has not yet begun.  The summer vegetable gardens are peaking with tomatoes, squash, melons, beans, cucumbers, and all the other seasonal crops.  The flower garden is bursting with the color of all the late-season bloomers, like dahlias, crape myrtle, hardy hibiscus, salvias, and the list goes on.

Late-Summer Food Crops

Lycopersicon esculentum 'Early Girl' JaKMPM
2016 has been a great year for tomatoes in the Pacific Northwest.

This has been a good season for tomatoes, and I am hearing from other gardeners that their crops are abundant.  We had both a mild winter and spring and tomatoes, which usually do not ripen until September in the Pacific Northwest, are turning red.

This year the season for commercial fruit and berry growers is about two weeks ahead of normal.  Last week I visited with the Market Manager of the Beaverton (OR) Farmers Market, and she said that apples that are usually brought to the Market in September maturing by mid-August.  Fall apples are now ripening in late summer!

Hardy Hibiscus

Hibiscus 'Tie Dye'
Hibiscus ‘Tie Dye’ is a late-summer gem producing 10-inch pink and white flowers with cherry-red eyes.

Since there is not much we can do about the weather, we should look to the garden and enjoy it and all the color it has to offer.  A favorite pastime of mine is walking through the garden in the early morning before the sun has gotten hot.  I like looking at all the color that the August garden provides.  In the past few weeks, I have been adding hardy hibiscus, (Hibiscus moscheutos), to my garden, and I am enjoying this late-blooming hardy perennial.

Often when people hear the word “Hibiscus”, they think of the tropical Chinese hibiscus (Hibiscus rosa-sinensis) from East Asia.  Instead, this hibiscus is native to the eastern United States, and I remind garden enthusiasts that if it can survive a winter in Michigan or Ohio, it will certainly survive a Portland winter.  One of its attributes is that it blooms later in the season, July-September, when many other herbaceous perennials are long gone. Check out your local garden center as they should have plants in bloom now.  In addition to flower color, (white, pink, red, and all shades in between), this hibiscus has a variety of foliage colors from solid green to dark red and almost black.

Hardy hibiscus like to be planted in full sun and need summer watering.  In fact, it is a wetland plant that grows well in continuously moist ground. That’s why I mix Black Gold Garden Compost into the soil before I plant to help hold moisture.

Fuchsia

Our Pacific Northwest climate is ideal for growing fuchsias and most are nonstop bloomers. All summer they attract hummingbirds, which is an added benefit.  A fuchsia that I saw in a garden late last summer was called ‘Dying Embers‘.  This prolific bloomer was a must-have in my garden this year, and it is not a disappointment with its small, very dark purple blooms.  I have my plant in a large pot filled with Black Gold Natural & Organic Potting Soil. As the August sun has been hot and bright, I am very glad that I did because it holds moisture while also providing good drainage and boost of organic fertilizer.

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Mid-to late-summer is the time to start seeds for fall planting.

Seed Starting

August is also the time to be thinking about the fall garden.  Most of our winters are mild enough to allow vegetable cultivation through the coldest months.  Sow seeds now for cool-season crops such as broccoli, cauliflower, cabbage, Brussels sprouts.  Start seeds now in seed trays with Black Gold Seedling Mix and plant them outdoors by late summer.  (Click here to learn more about starting plants from seed.) For gardeners with limited space, or those wishing to grow vegetables on a deck or patio, try starting leafy vegetables from seed in a pot using Black Gold All Purpose Potting Mix. Leaf lettuce is quick to germinate and can provide several cuttings before frost.

This is an ideal time of year to visit other gardens and see what is blooming.  I like to encourage gardeners to visit new gardens, talk with other gardeners, and learn what plants have done well, or not so well.  We often tend to visit other gardens in the spring and early summer, but many plant surprises can be also discovered in late-summer gardens.

Smart Summer Pruning and Deadheading

Removing the old, spent flowers from perennials, like this coneflower, will keep the plants flowering and looking great for longer. (photo by Jessie Keith)

Summer is not the time of year when most gardeners prune, but there are some definite advantages to summer pruning. It is easier to identify damaged or ill branches when a tree is in full leaf. When a tree is in full leaf it is also easier to identify branches that can be removed to provide better air circulation. A reminder: if you are going to do summer pruning on fruit trees, do it after the fruit has set.

Summer Pruning

Rosa-Perfume-Delight-2-JaKMPM
Deadheading modern rose varieties will encourage new roses to appear. (photo by Jessie Keith)

For those gardeners that have espaliered fruit trees, constant summer pruning is a necessity. With the tree sending out new branches, it is important not to let these grow too long but to keep them trimmed so the tree is kept properly trained and maintained. For gardeners that would like to be able to grow their own fruit trees, but have limited space, growing espaliered trees is an excellent option to consider.

There is confusion among gardeners as to when and how to prune hydrangeas. Some hydrangeas bloom on 2nd-year wood, so if a plant is severely pruned one season, it may take a full year for it to come into bloom again. There are other Hydrangeas, ‘Limelight’ is a good example, that bloom on new growth. This means it can be pruned at almost any time and still produce flowers. Check with your local garden center to learn the best time to prune your hydrangeas and still get flowers.

Check with gardening neighbors and garden experts to get additional tips on pruning. Find a neighbor that likes to garden and soak up some information. One of the best things about gardening is that most gardeners are very friendly, helpful, and like to share information.

growth buds that reside on either side of it.

Deadheading

Rhododendron-Scintillation-Dexter-Hybrid2-JaKMPM
When removing the summer seed heads from Rhododendron, be sure not to remove the new

“Deadheading” means is removing the old flower stems to make way for new. The word is used frequently with regard to rhododendrons and azaleas and refers to snapping or cutting off the area where the old flower was attached to the stem. With most rhododendrons and azaleas, this area is usually very visible which makes removal easy. Often, this is done for visual purposes because dried up flowers are not very attractive. Removing the flowers is also a way to prevent the plant from forming seed. When a plant forms seeds, it takes away nourishment that could be used for new growth. Be careful when removing the seed head because new growth buds reside on either side of it and should not be removed. These new buds will produce the new growth for the summer and this growth will then develop flower buds for next years’ bloom.DRoses are another plant that responds well to having the flower stems removed after the flowers are gone. This will encourage the plant to produce new stems and new flowers. Stem removal can also be seen as a way to perform some selective summer pruning and will help ‘open’ the bush up to allow for good air circulation. Just be sure to sanitize your pruners between plants to protect against any potential spread of disease.

Winter is not pruning season for all plants, even though most gardeners traditionally prune in the cold season. Sometimes what is traditional, is simply that, ‘traditional’ and may have no actual factual basis.

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For espaliered fruit trees, constant summer pruning is a necessity. (Image by Jessie Keith)

Preparing the Garden for a Hot Summer

Here in the Pacific Northwest, we have had record high temperatures already this spring. When the temperature is 100° F in spring, it is HOT!  Not that our weather pattern is ever predictable, but this year it seems to be even less consistent. With our mild winter temperatures, record rain, and a summer forecast as being hot and dry, our plants may suffer without some additional help.

In my own garden, I have become more aware of the need to get the right plant for the right place. What that means is that for full sun I make certain that I have a plant that appreciates this exposure. When we have temperatures in the triple digits, our soil can dry out very quickly and plants may suffer. While I realize that most gardeners have probably planted most of their containers and the bulk of their annual flowers and vegetables, we can still amend the top layer of soil to benefit the plants.

Amend Shrubs

Hydrangea Snow Queen
Hydrangea quercifolia ‘Snow Queen’ (oakleaf hydrangea) stands up better in the heat.

I have learned that some Hydrangeas are especially prone to suffering in hot weather. One of my favorites is Hydrangea aspera, which is a tall shrub. My plant is over 8 feet tall. It has such beautiful flowers that it is a showpiece in the summer garden. However, on hot days, the leaves will wilt as though it has not been watered for days when the soil is in fact moist. I recently added Black Gold Just Coir to the soil surface and worked it into the upper 1-2 inches of soil and this has helped. On the other hand, my Hydrangea quercifolia ‘Snow Queen’ (oakleaf hydrangea) stands up better in the heat.

 

Amend Vegetables and Flowers

In the vegetable garden, this is an ideal time to add Black Gold Just Coir or Garden Compost as either of these will help to hold soil moisture. June is the month many gardeners plant basil, and it is often planted in containers. In our garden, we always have a container of basil near the kitchen, and I use Black Gold Natural & Organic Potting Soil with RESiLIENCE®.

While many annuals may wither in the heat, an excellent summer bloomer is Lantana camera. While technically a tropical shrub, it is usually treated as an annual here. It thrives in the heat, blooms constantly, and the flowers attract butterflies. Lantana makes a wonderful container plant on a deck or patio because of the continuous bloom.

For the past few years, a signature plant in our garden is the red leaf banana, Ensete ventricosum. It has gorgeous large, red leaves and while a tropical plant, I have mine in large pots in a full sun location, and they do fine. My choice of soil is Black Gold Natural & Organic Potting Soil, and it seems to hold adequate moisture for these plants. A special treat that the red leaf banana provides is that by watering overhead, where the leaf meets the trunk, a small pocket of water will accumulate. This has become a very popular home for frogs to the delight of grandkids.

 

Water Regularly

Lantana, colors
An excellent summer bloomer for heat is Lantana camera.

When we have very hot days, and I see wilted plants that I know have adequate soil moisture, I will often spray them with a hose. This additionalwater seems to perk them up and within a period of less than an hour, they are looking fine.

Be aware of your plants and their environment and try to imagine where a favorite garden plant might naturally grow best in your yard. Don’t get too stressed if your plants wilt, take precautions, and then enjoy them, your garden, and the summer.

Mulching Gardens With Black Gold Amendments

When the drought is long, soils are poor, and money is short, one way to revitalize struggling garden plants is to protect their roots with mulch. Good mulches help to retain moisture, cool the root zone, and discourage weeds. The conventional wisdom is to mulch with wood chips or ground up bark, but both are very slow to decompose and can bind needed soil nutrients. The better option is to protect small beds and containers with organic-rich amendments that give back.

Garden Mulches for Soil Enrichment

Rich compost, peat moss, coir, or Black Gold Earthworm Castings are all amendments that double as mulches–alone or as home-mixed blends–in small ornamental gardens or vegetable gardens.  All offer needed organic matter, which helps soils better retain water and maintain porosity. They also offer structural and water-holding benefits.  For example, Black Gold Garden Compost Blend contains peat moss for water retention and compost give poor soils better aeration for easier establishment and performance.

Amendment mulching is often most effective in shaded areas because it helps to simulate conditions on the forest floor.  If you take a cross section of this “duff” layer, you’ll see that it’s mostly leaves or needles with a fine, dark layer that sits right on top of the earth.  It’s rich in decomposing organic matter, which is why shade plants are often surface rooted.

Landscape Mulches for Trees and Shrubs

This is also true of acid-loving plants, such as azaleas or camellias, which  develop a wide, shallow root system where the majority of the soil nutrition lies. In fact, without a yearly surface application of organic matter, these plants can suffer. All too often you see the surface roots of azaleas exposed after years without the addition of a mulch layer.  The organic matter is essential to keep their roots moist and cool, especially when drought descends. We recommend mixing a 1:1 of Black Gold Garden Compost Blend and Black Gold Peat Moss for acid lovers. Both products offer needed organic matter and peat moss is a little more acid, which benefits these plants.

Assess your favorite plants, planters, individual trees and shrubs to determine if they will benefit from this special treatment.   Apply a 2- to 3-inch layer of amendment around the base of the plant.  Always keep it few inches clear of the trunk to prevent bark-to- mulch contact, which can induce stress and rot.  Extend the mulch layer out to the edge of the drip line.

Don’t work the amendment in. Just smooth and pat it with your palm to flatten it out for better soil contact.   Moisten often with just a light spray or collected household water to keep these amazing shrubs and trees happy on minimal rainfall.  For areas with brief drought, mulch provides great short-term protection from an abnormally dry or hot summer.

As landscapes everywhere are being altered to be more efficient, don’t forget that amendment mulch can mean so much more to your plants.  If you already have bark mulch in place, the next best thing is to sprinkle amendments over the bark, so they can filter down and provide support the next deep water day or after a welcome summer cloudburst.

All About Growing Dahlias

Dahlia ‘Park Princess’

Dahlias come in all forms, from monolithic 12” dinnerplate monsters to tiny 2” pixie pincushion blooms, and colors—pretty much any shade except for true blue. So, you can never love just one. They thrive in the cooler seasons of early summer and fall and offer a botanical extravaganza of floral beauty with over 50,000 named cultivars and 20 wildly diverse forms. (Visit the American Dahlia Society (ADS) website to learn more.) Some are compact and perfect for containers while others are eight-foot monsters. All are wonderful and distinct in their own right.

Dahlia 'Mark Lockwood' - Copy
Dahlia ‘Mark Lockwood’

Dahlia Origins

The dahlias we grow in our gardens are hybrids of three high-altitude Mexican species, Dahlia coccinea, D. pinnata, and D. rosea, which were first collected in 18th-century Mexico and first cultivated in Mexico City under the care of the Spanish botanist, Vicente Cervantes (1755 – 1829). They were exported to the Royal Gardens of Madrid, Spain, in 1789, and began to appear in gardens across European shortly after. They popularized in the middle of the Victorian era (1850s-1860s), and by the early 1900s, there were thousands of varieties available across Europe and North America.

Dahlia 'Show 'N' Tell' - Copy
Dahlia ‘Show ‘N’ Tell’

Hybridizers come up with new dahlias each year. Many home gardeners prefer compact, heavy flowering border dahlias that don’t need staking. Five great performers recommended by Steve Nowotarski, the head of the ADS border dahlia trials, recommends the following three varieties: the party-pink decorative ‘Melody Pink Allegro’,  peppermint-striped ‘Princess Paige’, and magenta cactus-flowered ‘Pinot Noir’. For cutting, taller, long-stemmed varieties are best, such as the vibrant red and yellow ‘Show N’ Tell’, classic pink cactus-flowered ‘Park Princess’, and ‘Mark Lockwood’ with its lavender pincushion blooms.

Dahlia 'Taratahi Ruby'2 - Copy
Dahlia ‘Taratahi Ruby’

Growing Dahlias

Due to their cool, high-altitude origins, these sun-loving garden flowers grow best when weather is cool and humidity is moderate to low. When days are warm and nights are cool, they bloom and grow best. There is no real trick to getting their soil right. Like many plants, they excel in slightly acid to neutral, friable, organic-rich soil with very good drainage. Planting contained specimens in quality potting soil, such as OMRI-Listed Black Gold Natural & Organic Potting Soil with RESiLIENCE®, or heavily amending in-ground plantings with Black Gold Garden Compost, will ensure great rooting conditions. Keep the soil lightly moist, not wet, and feed flowering plants with a low-nitrogen fertilizer formulated for flowers.

Many dahlias are tall and require support—low tomato cages are perfect. Caging offers tall, large-flowered varieties needed support during heavy rains and wind –keeping top-heavy plants from toppling. Shorter varieties are easiest to tend as they don’t require support. All plants, tall or short, should be deadheaded regularly to keep new blooms coming until frost.

Tall dahlias staked in a tomato cage.
Tall dahlias staked in a tomato cage.

Overwintering Dahlias

Dahlias are tender perennials able to survive winters in USDA hardiness zone 8. In colder zones, their tuberous roots must be dug and stored indoors through winter. Dig dahlias after their tops wilt following the first light frost. When digging tubers, keep then intact and be careful not to damage their necks as this is where next year’s buds will appear. Gently clean and dry the tubers before storing them. Pack in a dry peat/vermiculite mix and store in a cool, dry basement, garage or root cellar no colder than 40 degrees Fahrenheit.

Once the threat of frost is past, plant again in spring to a depth of four to six inches. In cool weather, refrain from watering tubers directly after planting to avoid tuber rot. On hot summer days, be sure to water them regularly and provide potted specimens with shade during the hottest times of the day. Care for them well, and you will have wonderful garden color and cut flowers, even during the hotter days of the month.

Another great perk about dahlias is their value. These beautiful garden flowers are very reasonably priced. Swan Island Dahlias is a great one-stop-shop for hundreds of fantastic varieties befitting any garden. Plant a few this year and after one season, you will be hooked!

Dahlia 'Wheels' - Copy
The collarette Dahlia ‘Wheels’.

Soil Matters to Lavender

 

Distinguished by long thin wand-like flower stems, English lavender is the hardiest of them all.

The Serenity Prayer asks us to “accept the things we cannot change, the courage to change the things we can, with the wisdom to know the difference.”  If you’ve tried growing lavender with little success, maybe it’s time to identify what you can change to make this year’s garden a fragrant bee filled blend of drought-resistant lavenders for landscaping. It only takes a little wisdom to make a difference.

french lavender
French lavender is the commercially grown species popular throughout southern Europe.

Origins

Lavender comes from Europe where it has been grown in the South of France since Roman times.  There, the Mediterranean climate mirrors that of California where winters are wet and mild with long dry seasons extending from May to as late as December. These plants are naturally adapted to loose friable soils, sandy loam and fill soils that don’t pack down.  In areas with persistent humidity, extensive summer rain, and dense acid soils, lavenders languish.

A Need for Porous Ground

Naturally, fast-draining soils ensure the roots are exposed to plenty of oxygen during the growing season, and if irrigated or rain falls, it moves in and out of the root zone quickly.  Such porous ground, particularly on a south-facing slope, helps to counteract the slow soil surface evaporation caused by humid climates with stagnant air.

spanish lavender
Larger flowers and a shorter stature define the heat-tolerant Spanish lavender.

In northern California where rainfall can be very heavy in winter and soils are dense and extremely rich, lavender struggles despite its preference for the climate.  Fields now growing commercial lavender are plowed into mounded rows well above grade to enhance drainage and keep the root zone sufficiently aerated.

Amending Soil

Fortunately, the soil is among the things we can change by adding amendments that open its structure.  Prepare the natural soil by blending it with pumice and Black Gold Garden Compost Blend.  Use this enhanced mix to raise up the soil surface so the crown or base of the stem of the plant is above the surrounding grade.  This is also a good way to create soils that are perfect for rocky outcrops and raised beds where lavender thrives.

In San Francisco where conditions are cool and damp, growers prefer to mulch their lavenders with minerals such as washed sand or decorative gravel that help reflect heat back onto the plant. This porous material also creates a dry barrier between damp soil and the plant foliage to discourage mold.

Choosing a Lavender

varieties
All three species have yielded endless horticultural varieties to choose from.

Before you select a lavender for marginal areas, consult a local expert to find the best species and or variety to match your microclimate and soil conditions.  They vary in cold hardiness, size, and color from the cold-tolerant English lavender to a Spanish lavender to fill that super hot spot.  And for those romantics who love the notion of true French lavender in the garden, these plants will be the genesis of homemade tinctures, fragrant waters, sachets, potpourri, soap and a wide range of natural herbal cosmetics.

Once you know what to plant, select a sun-filled area and improve the soil for drainage, then plant in spring so there’s plenty of time to adapt your ground before the summer heat and fragrant flowers to come.

Effortless Garden Asters

Clouds of asters decorate the fall gardens at Chanticleer Garden in Wayne, PA.

Late-summer fields and meadows dotted with clouds of soft purple, violet, and white daisies are the surest seasonal sign that fall is here. These welcoming, cool-hued composites counter the warm oranges, yellows and burnished shades of goldenrods, perennial sunflowers, and black-eyed Susans. Garden-variety asters are even prettier, crowned in blooms that may venture into pink and magenta shades. For gardeners, there are no better flowers for the season.

Purple Dome aster (foreground) has some of the richest purple flowers for fall.
Purple Dome aster (foreground) has some of the richest purple flowers for fall.

Your garden’s pollinators and migrating songbirds would agree. Aster flowers attract bees and butterflies by the hundreds, and once pollinated, the seed heads become much-sought forage for songbirds. And, if these native flowers fare as well as they do in untended fields and byways, imagine how well they will do in your garden with little care.

 

Top Six Garden Asters

My top six asters for garden performance tend to be compact, tidy and heavy flowering. All have been proven to grow well in the regions of the Midwest and Mid-Atlantic where I have lived:

Wood’s Purple New York Aster (Symphyotrichum novi-belgii ‘Wood’s Purple’) —Loads of soft violet-purple flowers cover this low, shrubby aster (2-3’) in mid to late September.

October Skies Aromatic Aster (Symphyotrichum oblongifolius ‘October Skies’) —Many golden-eyed violet-blue flowers are the glory of this October bloomer. Plants reach an average of 2’.

Raydon’s Favorite Aromatic Aster (Symphyotrichum oblongifolius ‘Raydon’s Favorite’) —Blooming in late October to November with large, violet-purple flowers, this is a taller (3-4’) bushy variety that always performs well. Cut plants back by half in June for better flowering and tidier growth in fall.

Purple Dome New England Aster (Symphyotrichum novae-angliae ‘Purple Dome’) has a bushy habit (1.5-2′) and rich reddish purple flowers that really stand out in mid-fall.

Lovely Calico Aster (Symphyotrichum lateriflorum ‘Lovely) —Clouds of tiny pale lavender flowers bedeck this bushy (2.5-3’), dense aster in mid to late September.

Alma Potschke New England Aster (Symphyotrichum novae-angliae ‘Alma Potschke’)—One of the tallest of the set (3’), the deep magenta flowers sets this aster apart. These should also be trimmed back by half in June for better growth and flowering in fall.

Planting Asters

Aster novi-belgii
October Skies aster is a lovely mid-fall bloomer.

When interplanted with tidy bunch grasses and dwarf goldenrods, garden asters look naturalistic yet refined in the late-season garden. Planting can happen in fall or spring.

Start by picking a sunny, open garden spot. Naturalistic beds look most at home in gardens with soft, sinuous bed lines, so consider reshaping your garden to fit the character of your new plantings. Newly turned beds should be amended with a quality additive that encourages drainage while adding organic matter, such as Black Gold Garden Soil, though many field asters also grow well in clay soils.

Choosing good, complementary plants is essential. Your top picks should be vigorous, sun and heat loving, and have complementary habits, foliage and bloom times. When considering what asters to plant, talk with someone who knows and grows these plants in your area.

Other Perennials to Plant with Asters

Aster lateriflorus 'Lady in Black'
The small flowers of calico aster cover the stems of this October bloomer.

Floral compliments to all of these asters include Golden Fleece autumn goldenrod, Table Mountain willowleaf sunflower (Helianthus salicifolius ‘Table Mountain’), and the hybrid Happy Days sunflower (Helianthus ‘Happy Days’). All are compact and provide golden fall flowers that complement the cool colors of asters. Interplant with soft, airy grasses. The bunching, plush prairie dropseed (Sporobolus heterolepis), mounding Carousel little bluestem (Schizachyrium scoparium ‘Carousel’) and steely Elijah Blue fescue (Festuca glauca ‘Elijah Blue’) will add compact texture and provide winter interest.

The real beauty of these plantings is that they provide effortless late season charm and rare color that will light up any garden.

Monarch butterflies love aster blooms!

The Glorious June Garden

PRS Rose Show 2014
The Portland Rose Society Rose Show is a late spring event that occurs yearly in early June.
Cussonia spicata (Cabbage Tree)
The newest addition to my garden is a the delicate cabbage tree (Cussonia spicata).

Not that all 12 months are not great for gardening, but for me June is extra special. June is when I have already made many trips to local garden centers, and my containers on the deck and throughout the garden are almost all planted. My summer color baskets are blooming, the roses are at their peak performance, and the hummingbirds are being aggressive over what they perceive as their territory and favorite plants. Our water features have been cleaned and are running, the green tree frogs have returned, and our patio furniture is out on the deck. Plus, we have had more than our usual share of blue skies and sunny days, and we’ve been able to have multiple evening meals on our deck. This all makes me realize just how glorious the month of June can be here in the Pacific Northwest.

It seems as though hostas have been particularly beautiful this spring season. With our mild winter and early warm spring weather, they emerged early and look outstanding. Sometimes we forget how having different, interesting leaf textures and colors can create a beautiful and peaceful scene. I was particularly impressed with a recent garden that I visited with a bed of hostas that created just such a setting with beautiful and distinct leaf textures and colors. This gardener told me that earlier this season. he had applied a mulch of Black Gold Waterhold Cocoblend Potting Soil to help hold the moisture around the plants during what is predicted to be a dry summer.

Cornus kousa 'Venus'
Cornus kousa ‘Venus’ has gigantic flowers that appear in my garden in June.

There are many rose shows held throughout the month of June, and visiting one is an excellent way to gain some knowledge on growing roses. Since the roses being exhibited would primarily be from local gardens, they would likely be good performers for your area. Plus, attending a rose show is a good way to meet rose gardeners that are more than happy to share their knowledge. Despite the rose’s reputation of being high maintenance and requiring constant spraying, many new roses have been released that are quite disease resistant. Check with your local garden center on those that meet this requirement.

Dogwood trees provide spectacular blooms during much of June and this gives us an opportunity to see them as they actually grow and flower in a home garden. On a recent visit to the garden of a friend, I was in awe of his Cornus kousa ‘Venus’ in full bloom at the front of his house. The flowers measured 8-9 inches across and with the tree in full bloom, it was magnificent sight. Dogwoods generally like a soil rich in organic matter and adding Black Gold Garden Compost to the soil at the time of planting or as a top mulch on established trees would be beneficial.

Hostas at Joe's
The hostas are most spectacular in June.

I would be remiss without mentioning a new plant in my garden! It is cabbage tree (Cussonia spicata), and I have it in a large pot on our deck. I saw it at a local garden center and was not familiar with it. Since I liked the look, I bought it. I put it in a large pot using Black Gold Natural & Organic Potting Soil and around the base of the tree, I put three small plants of Acacia cognata (dwarf). Even though both plants are perennials, I would not expect them to survive a winter here without protection, so I will think of them as annuals and enjoy them all summer.

If you have some public gardens in your area, be sure to visit them during June. You may see plants being display in a way you have never thought of. Many garden organizations have ‘open gardens’ during June and often non-profit organizations have garden tours. Be sure to take advantage of these opportunities, you may meet some new plants and some friendly like-minded people.