Get it Growing: It pays to rid plants of faded flowers

Deadheading is an important but often neglected gardening technique. It refers to pruning off old, faded flowers from a plant as it blooms. It is most often done to annuals and perennials, but it is also useful with some summer-flowering trees and shrubs.

A number of advantages to deadheading make it worth the time and effort it involves. For one thing, it improves the appearance of a plant tremendously. Plants that bloom over a long period of time often end up with an accumulation of unattractive, dead flowers and seed pods mixed in with the newly opened blooms. This makes the plant look bad even with pretty flowers on it. If you keep the faded flowers pruned off the plant, it always looks fresh — as if it were just coming into bloom.

Removing the old flowers from many types of plants also will encourage them to bloom more and for a longer period. Annual plants, in particular, bloom for a time, set seed and then stop blooming and die. Regularly removing faded flowers prevents the plants from setting seed. As a result, annuals will respond by producing more flowers over a longer season in a continuing effort to produce seed. Many perennials will send up another flush of flowers if they are promptly deadheaded.

There are other advantages to preventing bedding plants, perennials and bulbs from setting seeds. Unless you intend to grow new plants from the seed produced, it is a wasted effort. Plants commit considerable resources to creating seeds. This effort could be redirected to growing more leaves, stems and roots, leading to a more vigorous plant and, perhaps, more flowers the next season. For annuals and perennials that self-seed, deadheading prevents unwanted seedlings from popping up all over the garden.

Depending on how the flowers are produced, deadheading may involve removing flowers on a single stem, such as gerbera daisies, removing faded clusters of flowers, as on yarrow, agapanthus or amaryllis, or removing faded flower spikes, as on snapdragons or veronica. If they are large enough, individual faded flowers can be removed from a stalk or cluster containing numerous flowers, as on rudbeckia, daylily and stokesia. As individual flowers in a cluster open and fade, they are removed, but buds are left in place to bloom. Once all the flowers have opened and finished, the entire stalk is removed.

When deadheading, always remove the stem that attaches the flower to the plant when you remove it. The idea is to remove any evidence that there was a flower at that location. Besides, headless flower stems are unattractive.

If you miss removing the faded flower and a seed pod has already started to develop, go ahead and remove the seed pod. You may still help encourage the plant to bloom longer or prevent the plant from wasting energy on further developing seeds.

If you do want to collect seeds from a plant or if you want it to self-seed in your garden, you must allow at least some of the flowers to set seed. The best way to handle this situation is to deadhead early in the flowering season and then let some of the last flowers set seed.

While you are deadheading, take the opportunity to groom your plants by removing damaged, unattractive foliage and dead stems or branches. Not only is this healthier for the plants, but it also keeps them looking their best. It is also a good time to inspect your plants for developing insect or disease problems and decide what kind of control, if any, is needed. Notice if any plants need to be staked or supported after months of growth in the garden, and attend to that as well.

A few summer-blooming trees and shrubs can benefit from deadheading. Crape myrtles, vitex and oleander are more likely to produce a second flush of flowers after the first is finished if you are able to trim back the old flowers or developing seed pods. Make your cut just behind a faded cluster or flower spike.

In a few cases, perfectly good flowers can be removed from plants. In the case of coleus and caladium, where the colorful foliage is the star, the flowers or flower buds are removed to encourage production of more attractive foliage. Flower spikes of herbs, such as basil, parsley and cilantro, are also removed to encourage continued production of flavorful leaves.

Once again, the plants that respond best to deadheading by extended flowering are annuals and perennials that bloom over a relatively long season as well as some summer-flowering trees and shrubs, such as crape myrtle, vitex, rose and oleander. Deadheading will not extend the flowering time of shrubs, such as azaleas or hydrangeas that bloom from a set number of buds, or perennials that bloom for a relatively brief season. But it can make them look more attractive and prevent them from wasting effort and energy on seed production.

Flowers lovers flock to Vermont bog for wild orchids

Each spring and summer, a Vermont bog yields a rare spectacle — hundreds of wild orchids in bloom, drawing visitors from around the country.

The bulbous pink and white showy lady's slippers (Cypripedium reginae) are on full display among the ferns, bushes and chirping birds at Eshqua Bog in Hartland.

This particular orchid, considered rare in Vermont and a number of other states and different from the more common pink lady's slipper, thrives in Eshqua, because of the wet, sunny conditions, with soils containing peat and lime.

Mary English drove about an hour from Landgrove, Vermont, to see the orchids on Thursday. When she arrived, she had the bog to herself.

"I just wandered through by myself. It was very special. It's like being in a South American country," she said.

A boardwalk allows visitors of all ages and abilities access to the bog and an up-close look at the plants.

"Gosh, aren't they beautiful?" said Heather Crawley, of Maryville, Tennessee, as she studiously photographed the orchids with a special lens on Thursday. "To think it's natural, too."

Visitors can also walk a half-mile trail.

The area is technically a fen because it's less acidic than a bog and fed by groundwater containing nutrients like calcium and magnesium from the area bedrock, according to the Nature Conservancy, which owns and manages the preserve along with the New England Wild Flower Society. The sanctuary includes an 8-acre (3.2-hectare) wetland and 33 surrounding acres (13.4 hectares).

Other orchids also bloom, like yellow lady's slipper in late May and early June and the white bog orchid around now.

The lime-rich groundwater also helps to yield pitcher plants, insectivorous sundew and other plants.

But the orchids are typically the main show for visitors.

"The orchids love it at Eshqua, and people love to see the orchids," said Rose Paul, of the Nature Conservancy.

Getting bees hooked on flowers with nicotine

While some researchers have been busy developing a possible vaccine to help humans beat their nicotine cravings, others have been getting bumblebees addicted to the stuff. But the experiment wasn't just an exercise in getting the bees buzzed, it was an investigation into whether or not the drug could influence the insects' ability to learn the color of flowers. Hint: It can.

They sure do love their bumblebees over at Queen Mary University of London. Researchers there have previously taught the pollinators how to push a ball around a playing field, and pull a string to get food rewards. In a further demonstration of how a creature with a brain about the size of a pin head can be trained to execute particular behaviors, researchers there used nicotine-laced nectar on artificial flowers to see if they could get the creatures to show a preference for one color over another.

So they laced blue flowers with a plain sugar solution and purple flowers with a sugar solution containing nicotine. They then set 60 different bees lose in their artificial garden to see how they behaved. Sure enough, the bees showed a clear preference for the nectar that was doped with nicotine in the purple flowers. Interestingly though, the bees were repelled by the nicotine-containing flowers if the concentration of the chemical was too high.

The researchers then reversed things: They laced the blue flowers with the nicotine solution and the purple flowers with the plain nectar. The bees continued to fixate on the purple flowers however, showing that they had associated the color with the reward, even if they could get a nicotine buzz by visiting the other flowers (pin-head-sized brain, remember?).

"Flowers typically reward pollinators 'honestly' with rewards such as sweet nectar, but nature's trick box is endlessly resourceful, said professor Lars Chittka from QMUL's School of Biological and Chemical Sciences. "Some plant species gain an unfair advantage over competing species by spiking their nectar with addictive substances, such as nicotine in tobacco flowers."

While the experiment might seem a bit obvious – of course bees would prefer a buzz-bringing solution over plain sugar water – the researchers say it opens the door to wide range of future studies analyzing ways in which plants might outcompete each other for the attentions of insects that can spread their pollen.

"I am convinced that what we found with this study is just the tip of the iceberg," said co-author David Baracchi who is now based at the University of Toulouse in France. "Plants may have hundreds of metabolites in their nectars and it is possible that many of them have to some degree similar psychoactive properties."

Alys Fowler: thinking of a green wall? Give climbing plants a go instead

On the walk to work, I pass a half-dead green wall. It had gone the way of many green walls, which are often far more work than anyone wants to let on. So I pondered the merits of green walls versus climbers. Climbers won. These are plants that actually want to grow upwards across something vertical and require no more effort from you than giving them something to grow on. Putting up wires or netting may seem a faff, but when you’re on to your third replacement plant and the drip irrigation is still overwatering a particular section of your green wall, vine eyes and wire tensioners may suddenly look more interesting.

One reason people are drawn to green walls is their suitability for small spaces. Many climbers are perfectly content with life in a container, and watering a pot is much more simple than trying to water a wall.

If you decide to grow your climbers in a container that’s, say, the size of a window box on the ground, you’ll have a hard time. Even annual climbers such as sweet peas and climbing nasturtiums need more room for their roots. Most climbers, particularly perennials, have evolved to grow in woodland, whether that’s in the depth of shade, such as ivy, or at the edge, they need something to climb and more often than not that’s a tree. Woodland soils are deep, rich and cool; this is the opposite of many pots that are shallow, exposed and often very hot. Thus, you need the deepest pot you can find. A good nursery-grown climber, whether it’s for a pot or the soil, will be grown in a long tom pot, which is taller than it is wide. For a perennial climber, ideally you’d like a 15-20 litre pot; something you can just about get your arms around. Although this may seem too big, it’s a false economy to use something smaller; you’ll have to water endlessly in summer and eventually re-pot. A five-litre nursery-bought climber potted into a 20-plus litre pot will happily fill a 2m x 3m wall (provided it’s got support to climb up).

The Boulevard collection (‘Picardy’, ‘Parisienne’, ‘Cezanne’ and ‘Countess of Wessex’ are my favourites) are compact with flowers at a height you can see them. Use a rampant Clematis montana or C. cirrhosa and you may find someone else is enjoying the blooms in the flat above.