Friday, June 21, 2013

Irrigation Police: Wasting Water And Killing Your Plants

Clive the Pig from Pennywell Farms in Devon, England.
His expression embodies our disgust for the amount
of rain we have received this June.
We have been buried with water this June in New England.  As of June 18th, we have had 11.13 inches of rain (Blue Hill Observatory), and that makes it the fourth wettest June on record with 12 days left to move up.

That is 2/3rds of an inch a day, when most gardens in this cooler weather could live off that amount in a week.  April may have been a little dry, but this has been crazy.

Yet through all this rain, with a few dry days thrown in, homeowners and commercial spaces have been running their irrigation.  During downpours, the day after rain, the day before rain, and in many cases some irrigation systems run every day.


Now, I have to be careful because I am not perfect.  I eat red meat, I use Round-up(sparingly), I like Impatiens in deep shade, I wear leather (not pants or crazy stuff), I like 'Real Housewives of New Jersey', I am a man, and my system came on once in the rain when the sensor had fallen down.


No system is perfect, but with a little bit of attention everyone can save water, money and have healthier gardens.

This system is pouring out water, mostly on the parking
lot the day after receiving an inch of rain.  In the previous
week we had received over 4 inches of rain.  I had some
other pictures but didn't want to single out
 individuals or houses.
There is plenty of technology that will help you to efficiently water your lawn and gardens and minimize the cost of water if you are paying for town water.  Every system should have a rain sensor, this will not allow the system to run if it senses water or is still wet from a recent rain.  There are some new and very sophisticated systems that access local weather data and can adjust output based upon past rain, temperatures and forecast weather.  Some systems even use sensors in the ground to determine watering needs.  

Grey Water is also becoming popular for watering gardens.  This has become a necessity in certain parts of the world.  I remember, at a firm that I worked at a number of years ago, a project in Israel where gray water was the only way to keep the gardens watered due to local restrictions.

Not only is too much water a waste of water and money, but most plants do not appreciate sitting in wet soil. Most plants, especially grass need to dry out a little between waterings and prefer regular deep watering  than everyday watering.  Daily, light watering is the worst for all plants since it makes the plants send roots to the surface to collect water and this makes them very intolerant of drought.  Deep watering(by rain or irrigation) allows the roots to go deep where it is cooler and water stays longer.

Too much water also brings disease.  Disease weakens plants, which brings insects, which brings pesticides and a whole nasty cycle.

Talk to your irrigation contractor or find a new one that utilizes some of these new technologies to minimize waste and improve the health of your lawn and gardens.

If you don't want to make this investment, take a look at your system and become familiar with how it works.  So many irrigation companies turn on the systems each spring and they irresponsibly put way too much water on.  Once a week to provide and inch+ of water is enough given normal temperatures and rain.  If you don't know how long it takes to deliver an inch of water, put a receptacle on your lawn that has vertical sides(for proper measurement).

Different types of irrigation heads deliver different amounts during a set period so check out the different zones of your garden.  This doesn't have to be exact and could be a cool project for your kids on a summer day.  Generally sunny areas need more water than shady areas, so you might have the sunny areas run longer than the shady areas, or maybe they come on an extra day of the week.  The new controllers are quite sophisticated and people rarely use them to their potential.

If the weather gets really hot then you can increase the time or frequency and adjust back when it cools down.  No one setting will work for the whole season.  With a little knowledge and some adjustments you can save a lot of water and a lot of money.  For some of the systems I see running, I know that they could save over a thousand in water bills and who knows what else with regard to plants.

Water responsibly or the Irrigation Police will find you.




Friday, June 14, 2013

Flowering Dogwoods Are Beautiful And Versatile Trees.

Cornus florida in full flower  ©2013BDG
I just love Dogwoods.  They are one of the most versatile ornamental trees and they provide that valued four-season interest.  I rate it slightly behind my favorite, Stewartia psuedocamellia, but it performs well in all five of the criteria I use in rating ornamental trees:  Habit, flower, bark, fall color and winter interest.

Pink Cornus florida flowers  ©2013BDG
There are many different types of plants in the Cornus genus, including a wonderful ground cover called Cornus canadensis and a number of shrubs.  In New England, most of the planted trees are either the native Cornus florida, the Korean Dogwood (Cornus kousa) or the Rutgers Hybrids, which are a cross between florida and kousa.  There is also Cornus mas, Cornus alternifolia, Cornus controversa, Cornus chinensis and several others, but the most significant in our landscape are florida, kousa and the hybrids.

These three major species flower in white and pink colors with a broad variation in each color range.  The whites range from pure white(f. 'Cherokee Princess', k 'Milky Way') to cream (k 'National') to greenish-white(k 'Ticknor's Choice').  On the pink side they range from delicate pink(k 'Stellar Pink') to deep red-pink (f 'Cherokee Chief).

Pink Cornus florida in bloom
before leaves emerge ©2013BDG
Arguably, the best floral display by any tree is the native Cornus florida, that is the first Dogwood to flower in late April or early May.  What makes this display so amazing is that it comes before the tree has leafed out and the flowers can literally cover the whole tree.  Of all the Dogwoods, it has the most interesting horizontal, tiered form and with minimal pruning can be a stunning specimen that looks as interesting in winter as during the summer.  Unfortunately this species suffers from a disease called anthracnose that without care will shorten their life.

In its native habitat, it is considered an understory tree in woodlands, so it prefers some shade and will suffer in full sun or dry conditions. It has a red berry that forms in summer from the flower and can be distinctive in the fall

Cornus kousa in flowers.  Notice the linear appearance
of flowers on the branches  ©2013BDG
The Korean or Kousa Dogwood is the last to flower  in June and some cultivars are known for carrying their flowers through much of the summer.  'Summer Star' is one of the longer flowering cultivars.  The Kousa dogwood is different in that it flowers about a month later than florida, when the leaves have already emerged.  The flower displays can be just as impressive and are offset by the green leaves.

Close-up of dense kousa flowers  ©2013BDG
A distinct look of the Kousa in flower is the long line of flowers along the branches.  There appears to be a flowing, linear display of flowers as you can see in the image.  The Korean is much more sun tolerant and is better suited in a hot, sunny location as opposed to the florida species.  Its habit is more upright than the florida species, but still develops nice horizontal branching.  

A very cool aspect of the Korean Dogwood is the round red berry that develops in the late summer.  They persist on the tree into winter and can be quite decorative in the fall.

Years ago someone told me that fruit, inside the outer skin, is edible, so I tried it.  Cardboard is edible too but I choose not to eat it often.

In comparison, I feel that the native florida tends to be broader and more structural, while the kousa is a little more upright with a traditional tree shape.

Cornus x 'Constellation' hybrid  ©2013BDG
The Rutgers hybrids were developed as a result of crossing florida and kousa.  These hybrids flower in between its two parents and the flowers emerge just before the leaves and finish after the leaves have emerged.  It is a prolific flowering tree like its florida parent but doesn't have some of the cultural problems.  Generally it lacks the graceful horizontal form in youth but the branches do settle with age, yet it is no substitute for the beautiful form of the florida species.

'Constellation', Rutgers Hybrid flower  ©2013BDG
All of these wonderful species have beautiful and variable red leaves in the fall and an interesting checkered and peeling bark.

There is a dogwood for just about any space in the garden and I feel it is one of the best and hardest working trees you can find.  Because they are relatively easy to propagate and are moderate growers, Dogwoods are not a very expensive tree.

Here in New England we get to see these trees flower from April to July and if you have the space for multiple specimens you can have trees that provide year round interest and flower over a four month period.








Friday, June 7, 2013

Contrasting Colors: Flowers and Foliage In The Garden.

Five different Hostas, Epimedium, a chartreuse Heuchera and some
dwarf evergreens provide a broad range of analogous colors and
and some variable foliage textures and shapes.  ©2013 BDG
While it is hard at this time of year to pause and appreciate plants and gardens, for fear of being buried in weeds and new growth, I think this is the best time to see gardens before the onslaught of heat and bugs.  The colors are so rich from the cooler weather and spring moisture, and the plants are full of energy from their spring growth spurts.

By now the spring bulbs are gone and the first round of early perennials are finished and there is lots of work to do in the garden to cut back, weed, stake, weed, sow and of course weed.

The ground foliage of the Alchemilla and a wonderful spreader whose
name escapes me really help to show off the weeping Japanese Maple,
and the foliage of the ground covers contrast nicely too.  ©2013 BDG
While flowers are always an integral part of a garden, they don't have to be the only part to provide interest throughout the season.  I love putting together plants with varying textures, leaf shapes and leaf colors to provide contrast and interest.  The great part about this design principle is that the benefits last all season, rather than the relatively short time you get from flowers.  There are endless flower combinations you can use to bring stunning color to the garden, but often they only last for a few weeks until the next one comes along, and sometimes people just don't have the time or space to nurse their gardens to this level of achievement.

First flower on my Nicotiana contrasting with a
pale purple Verbena.  ©2013 BDG
Contrasts can be drastic with complimentary colors like chartreuse Alchemilla (Lady's Mantle) flowers in front of a purple/red dissected Japanese Maple or they can be subtle variations of green from several different plants.  Contrasts in the form of different leaf shapes and leaf textures are also dramatic and can help to reveal an individuals plants characteristics as it is seen in contrast with another.

People have written books and defined their careers (Gertrude Jekyll)on the subject of color, so I won't pretend to offer anything definitive here.  

If you look at the color wheel, you can see that the greatest contrast comes from colors on opposite sides of the wheel and these are considered complimentary colors.  Yellow/purple, orange/blue and green/red are ones commonly used in gardens and they tend to provide 'pop'.  These complimentary colors are seen in several of the images on this page.  

On the other hand for a gentler, less jarring approach using analogous colors that are adjacent to each other on the wheel will provide a more soothing and subtle look.  The yellow and green foliage image on the top is an example of using analogous colors.  I find that these subtleties show best in shaded gardens where the light isn't so harsh as to obscure the differences.

I think the most important advice is to use those colors and color combinations that appeal to you.  There are general rules, but in gardening, I feel that these rules should be constantly broken, because at the end of the day you are living in your garden, not your neighbor or some colorist who said that Aubergine, Black and Chartreuse are the 'hot' colors.  I just made that last part up.

When visiting a nursery I will often gather several plants together to see how they look, but one of the best ways to see how combinations work is to visit other gardens.

Here are some great ones in the area:






This is more of a foliage contrast with the dissected leaves of the big
Aruncus and smaller Astile contrasting with the scalloped leaves
of the Ligularia and the Alchemilla.  The color contrast of the reddish
Ligularia really sets the other green plants off and keeps the bed
from feeling so... green.  ©2013 BDG
A new plant called Alchepeta, combining the flowers of Alchemilla
and Nepeta.  Another contrast of complementary colors. ©2013 BDG
'Niobe' Clematis flowers really pop off the green foliage.  ©2013 BDG



Saturday, June 1, 2013

Ricin And Other Poisons Found In Our Plants.

Very cool, but deadly, Ricinus flower
head  ©2013 BDG

Ricinus or Castor Oil Plant is considered one of the most poisonous plants in the world, and it is the source of the poison Ricin that has been in the news recently.  I made this connection recently while listening to a program on NPR talking about the deadly nature of the toxin and realized that I have had this ornamental annual in my garden before.   I knew this plant was poisonous, as are many common plants in my and almost everyone's garden, but I had no idea that it was 'that' plant.



Both Castor Oil and Ricin are derived from the seed of the plant.  The oil is not toxic and has medicinal and industrial uses, while Ricin is a deadly poison.  All parts of the plant are poisonous, to a lesser degree, but the seeds are the most poisonous with a few capable of killing animals and children.  An article by Cornell University on Ricinus provides a comprehensive summary.


A trio of poisonous plants in my garden: Yew,
Rhododendron and Azalea.  ©2013 BDG

This led me to take a look at poisonous plants in general.  Most everyone in New England has a plant considered toxic in their garden, however, poisoning or death from plants is not a regular occurrence.  Here is a list of common garden plants that may be poisonous, as well as the ASPCA Poisonous Plant List.


Wisteria, Rhododendrons, Azaleas, Laurel, Yew, Hydrangea, Daphne are some common woody plants that have poisonous parts.  While most would require significant ingestion for serious consequences, it is good to know that some very common plants can be dangerous for animals and young children.  Daffodils, Delphinium, Monkshood, Lily of the Valley, Iris, Foxglove, Bleeding Heart, Mums, English Ivy and Euphorbia are some common perennials with parts that are toxic to animals and people.

Hydrangea flowers can be toxic, but at size
of a small soccer ball I am not sure how
to eat this.  ©2013 BDG

With animals that love to dig and chew, it is recommended that you not keep these plants in areas where they have regular access.  For children, it is the decorative parts that are most often a concern.  You may remember Yew plants when we were kids that had those irresistible berries that were ammunition in battle.  The berries are quite poisonous.  Yews happen to be dioecious plants(either male or female plants) and most plants in the trade nowadays are male that don't bear the berries.


Daffodil bulbs are poisonous which is why Squirrels and other furry varmints don't dig them up.  The critters know this and planting Daffodils around other sensitive bulbs can minimize damage.  Foxglove (Digitalis) is used as a common heart medicine, but can be dangerous if ingested.  I didn't realize that Hydrangea flowers can be toxic, so definitely not a flower I will be adding to the top of my salad.

The roots of bleeding hearts are toxic.  ©2013 BDG

We have lived with many of these plants in our gardens for years and we, our children and our pets have survived, but it is always good to know a little more about potential dangers around us.  It is not necessary to go out and dig up every potentially dangerous plant, as many of these plants may only cause stomach upset or diarrhea with minimal consumption.  However, with all of the introductions of exotic annual plants from sub-tropical and tropical parts of the world, it might be good to be cautious placing them in containers that are easily accessible to our young children and animals.


As cool as the Ricinus plant is with its foliage and flower, I don't think I will bring it into my garden while I have two curious little Beagles and a teenage son.