Wednesday, December 06, 2006

Should I put fish in my pond?

Fish add movement and character to any pond, and they are an important component in a healthy aquatic ecosystem. They also eliminate mosquitoes and other insects that breed in water. Many fish species also eat aquatic plants, however, so it is important to keep their numbers at a reasonable level. Many aquatic gardeners keep ornamental carp known as koi in their ponds. These fish are available in a myriad of colors and patterns and can live for a very long time and grow quite large. Goldfish are very adaptable and can survive the winter in your pond if it does not freeze to the bottom and a portion of the water surface is kept free of ice to allow for gas exchange.

If you choose to keep fish in your pond, make sure they don't have the opportunity to escape to natural waterways in your neighborhood where they can compete with and displace native fish species.

What can I do to keep algae out of my pond?

The algae is growing because the nutrients are available to support its growth. A small amount of algae is good for the aquatic garden since it absorbs excess nutrients in the water, helping to keep it pure. Uncontrolled algal growth depletes oxygen in the water and makes the water inhospitable for the fish.

Make sure that you have not overstocked your pond with fish. Also make sure that you are not overfeeding your fish. Uneaten food is source of nutrients that translates into algal growth, and a large population of fish produces a large amount of nutrients when they excrete waste products. A pond biofilter can help remove excess nutrients and keep the water clear. You can also add water to the pond periodically to dilute nutrients if you have an overflow system that can drain excess water out of the pond. Barley straw discourages the growth of certain types of algae. Pond supply firms sell barley straw products that can be submerged in your pond. Dyes are available that can be added to the water. The black material absorbs the sun's light energy and deprives the algae of the light it needs to carry out photosynthesis and survive. Dye products have the added advantages of protecting your fish from predators and concealing plumbing and pots in your pond.

Many aquatic plant gardeners are tempted to drain the pond, clean it, and start over with fresh water when confronted with algae. This is usually counterproductive since the excess nutrients that cause algae to grow build rapidly in the fresh water. Frequent water changes and cleaning can make for drastic changes in pond pH and are stressful for fish and other aquatic life. Only drain and clean your pond when a substantial layer of decaying organic matter has accumulated at the bottom.

Can I keep my plants in the pond during the winter?

That depends on which plants you are growing. Some aquatic plants are perfectly hardy and can spend the winter in the pond. Hardy water lilies and lotus can simply be moved to a lower depth in the pond. Hardy plants such as cattails, water iris, and rushes can stay near the water's surface where they normally grow. Tropical plants such as tropical water lilies, cannas, and papyrus cannot even tolerate cold water, so they must be kept in a greenhouse over the winter or they must be started from new divisions every year.

Can I grow any canna in my pool?

Cannas are native to moist areas and many do quite well if grown in water, as long as they are not submerged too deeply. The cannas in the pool at the U.S. National Arboretum are varieties of Canna glauca or hybrids between Canna glauca and other canna species. They may also be grown in bog plantings where the soil is constantly saturated. Garden cannas are surprisingly adaptable to wet conditions and some may be grown in water if temperatures are warm. The rhizomes of all cannas rot in cold, saturated soil, so they cannot live over the winter in the aquatic garden.

How should I prune my roses?

Prune your roses lightly in autumn, removing canes long enough to be whipped by winter winds and those canes with signs of disease. Pruning to remove remaining dead, diseased, and damaged canes is done in early to mid-March just before growth starts. Species and climbing roses are pruned by removing entire canes all the way to the ground to encourage an open, vase-shaped habit. The rest of the roses get pruned to knee height at an outward facing bud. You can do some light pruning to shape the plants during the summer as needed.

What can I do about black spot on my roses?

Roses are not the easiest plants to grow in the Washington, D.C. area. Our climate is perfect for the development of black spot, a fungus that can defoliate and weaken plants if not kept in check. Fortunately, antique, heritage, and species roses are generally more resistant to diseases and pests than hybrid tea roses. When control measures are needed, the Arboretum practices Integrated Pest Management (IPM) to control pests and diseases. The practice combines planting disease resistant varieties, promoting proper cultural techniques, and careful monitoring of pests combined with spraying, natural control methods, and tolerance of minor amounts of damage. To minimize black spot problems and limit the amount of spraying you need to do in your own rose garden, follow these tips:

* Promote air circulation and light penetration. Prune trees and hedges surrounding the rose garden low so that sunlight and breezes can quickly dry the foliage after morning dew or rain. Keep companion plantings at a distance to allow maximum exposure of the rose foliage to sunshine and air.
* Eliminate overhead irrigation. Water the soil with a soaker hose and keep the leaves dry. Black spot spores need water on the leaf surface to germinate.
* Prune cankered canes. Cankered stems bear black, dead areas that harbor the fungus over the winter. Prune them out, preserving more vigorous healthy canes, to prevent infection of spring foliage.
* Apply lime sulfur just before bud break in spring. This treatment delays the onset of black spot and powdery mildew infections for several weeks, even if weather is favorable for infection.
* Apply a fungicide based on neem seed extract beginning when leaves are fully expanded. Neem products are not as toxic as conventional fungicides and have the added benefit of controlling many rose insect and mite pests. They only work to prevent new infections, so spraying must be done on a weekly basis as long as weather is humid or wet.
* Apply conventional fungicides as a last resort. If the weather is dry in early summer, and you have applied neem every week, you may not have a black spot problem at all. But if you miss an application, or daily rain and dew create ideal fungal infection and growth conditions, you may need to use a conventional fungicide. Use a fungicide containing chlorthalonil, thiophanate methyl, or propiconazole. It's best to rotate different fungicides, never using the same one two times in a row, to prevent the fungus from developing resistance to the fungicides.
* Tolerate some damage, especially late in the season. Heritage and antique roses generally bloom in late spring and bloom only sporadically throughout the rest of the season. In July and August, with the flowers gone, the plants attract little attention and some black spot can be tolerated without permanent harm to the plants.

Basic Plant Requirements

Anyone interested in gardening has one question in mind when choosing a new plant: Will it thrive in my garden?

Many factors come into play to determine whether or not a plant will perform well for you. Each kind of plant has its own needs and requirements. Some plants, like the dandelion, are tolerant of a wide variety of conditions, while others, such as the pink ladyslipper orchid, have very exacting requirements. Before you spend the time, effort, and money attempting to grow a new plant in your garden, it is best to do some research to learn something about the conditions that the plant needs to grow properly.

Here is a brief description of some of the environmental parameters that influence plant growth:

Daylength is usually the most critical factor in regulating vegetative growth, flower initiation and development, and the induction of dormancy. Plants utilize daylength as a cue to promote their growth in spring and prepare them for the cold weather. Many plants require specific daylength conditions to initiate flowers.

Light is the energy source for plants. Cloudy, rainy days or the shade cast by nearby plants and structures can significantly reduce the amount of light available. Shade adapted plants cannot tolerate the bright light of full sun. Plants survive only where the amount is within a range they can tolerate.

Plants grow best within an optimum range of temperatures; and the range may be wide for some species, narrow for others. Plants survive only where temperatures allow them to carry on life-sustaining chemical reactions.


Plants differ in their ability to survive cold temperatures. Some tropical plants are injured by temperatures below 60°F. Arctic species can tolerate temperatures well below zero. The ability of a plant to withstand cold is a function of the degree of dormancy present in the plant, its water status, and general health. Exposure to wind and bright sunlight or rapidly changing temperatures can also compromise a plant's cold tolerance.

Heat tolerance varies widely from species to species. Many plants that naturally grow in arid tropical regions are naturally very heat tolerant, while subarctic plants and alpine plants show very little tolerance for heat. High night temperatures are often the most limiting factor for many plants.

Different plants have different water needs. Some tolerate drought during the summer but need winter rains. Others need a consistent supply of moisture to grow well. Careful attention to the need for supplemental water can help you select plants that need a minimum of irrigation to perform well in your garden. If you have poorly drained, chronically wet soil, you can select lovely garden plants that naturally grow in bogs, fens, and other wet places.

The ability of plant roots to take up certain nutrients depends on the pH, which is a measure of the acidity or alkalinity of your soil. Most plants grow best in soils that have a pH near 7.0. Most ericaceous plants such as azaleas and blueberries need acid soils with pH below 6.0 to grow well. Lime can be used to raise pH and materials containing sulfates such as aluminum sulfate and iron sulfate can be used to lower pH. The solubility of many trace elements is controlled by pH, and only the soluble forms of these important micronutrients can be used by plants. Iron is not very soluble at high pH and iron chlorosis is often present in high-pH soils, even if they contain abundant iron.

Tuesday, September 19, 2006

Spring Garden Tips

Josh Gray

Gardeners, it's time to put your gardening skills to the test. If
temperatures are cooperating, the merry months of May and June
will be your busiest until September, with planning, planting,
and patio projects to lead the way into summer. Don't be fooled
by a late frost; find out the mean freeze date in your area, and
be sure soil is warm and workable -- not too wet, not too dry --
before putting tender plants in the ground.

By the time your garden is prime for planting, you should already
have a plan of attack in place. Are you going to be planting
bulbs, annual, more perennials, or a vegetable and herb garden.
Maybe even all of the above if you are blessed with a big yard.
Once you have a plan, its time to acquire your new plants. The
quickest and easiest way is to buy your plants online. Everything
you need from seeds, bulbs, and tools can be found through online
merchants, and many sites even offer online coupons for increased
savings. Small starters usually cannot be shipped directly to
you, but can be sent to a store close to home for pick-up at your

If you are going to be putting in sensitive vegetables like
cucumbers, squash, tomatoes, and melons, you may wish to wait a
few weeks after the last thaw to ensure they don't get damaged by
an extra cold night. If you want to plant early, consider sowing
heartier vegetables like potatoes, peas, beans, carrots, and
lettuce. Not sure about when to plant, then ask an expert at your
local gardening center.

For all the beautiful colors of spring, consider planting both
annual and perennial flowers. Although your perennials will still
be around from last year, you may want to add a few of your
favorites to replace flowers lower on your list. Annuals are an
important part to every garden. They bring some of the richest,
most vibrant colors to your garden. Plant your annuals from
starters if you want an early spring bloom. Make sure that you
plant annuals in areas of your yard that get at least five hours
of direct sunlight per day. Don't be cheap on the plant food and
watering, and you will ensure your flowers get the right
ingredients for full, healthy blossoms.

Once the initial preparing and planting are finished, you can sit
back and relax, letting your sprinklers do the rest of the work.
If you work hard early on, your hardest task in summer will be
choosing which flowers to make cuttings of and create bouquets
for the kitchen and dining room. Enjoy the fruits of your labor…
until next spring.

Copyright © 2005 Josh Gray
Josh Gray, President of UC San Diego's Gardens Club, is a
consultant to This online coupon website
provides free coupons and discount codes to many favorite
gardening websites on their home and garden coupons page.

How To Plant Potted Roses

Angie Noack
It wasn't too long ago that no serious rosarian would even
consider having a potted rose on their property except for,
maybe, last minute emergencies where they had run out of space
but couldn't resist buying just one more plant.

Times have changed and potted roses have a place in the lives
of condo and apartment dwellers, city slickers who live in
areas where there isn't a tree in sight, and anyone who has a
spot on their lawn or garden in need of the beauty that only a
rose can deliver.

Not all roses are good candidates for growing in pots. The
following varieties have been found to do best. Feel free to
try any variety that you want, even climbers, and see how they
make out.

All that Jazz


Blush Noisette


Cecile Brunner

Clotilde Soupert

Green Rose

Gruss an Aachen

Hannah Gordon


Katharina Zeimet

Mrs. Oakley Fisher


Perfume Delight

Precious Platinum

Sea Foam

Sexy Rexy

Souvenir de la Malmaison

Stanwell Perpetual

The Fairy


Whiskey Mac

Planting potted roses is a relatively easy task as long as you
do your planting in the Spring after any chance of a frost is
long past. If you live in climate zone 6, or warmer, then hold
off planting until autumn when the ravages of July and August
are far behind.

When you're ready to plant, choose an appropriate sized
container with drainage holes. Make sure that the container has
enough room for your plant to grow without having to transplant

Fill the container with garden soil that has some compost or
organic fertilizer mixed in.

Dig a hole that's a bit bigger than the root ball, knock the
rose loose from its shipping container, and plant it.

Dig a shallow trench or moat around the base of the plant to
hold water, and water well.

Potted roses are susceptible to the same diseases as garden
roses are, and they require feeding, pruning and all of the
other rose care basics. Potted roses aren't less work or
responsibility for you, they are simply more space-saving than
a regular rose garden is. Don't treat your roses as if they
were ordinary potted plants or you will lose them.

People are constantly asking if they can grow potted plants
indoors. The answer is: "maybe, but it's a risky proposition".
That's because roses need high humidity and a lot of direct
sunlight. High humidity conditions do not usually exist inside
of most airconditioned homes these days. However, if you live
in a hot, steamy area, and you don't have air conditioning,
then you can probably get away with it as long as you pick a
sunny spot.

Of all the rose varieties that are likely to survive indoors,
miniature roses are your best bet. Miniature roses are actual
roses which have been bred to grow into small and compact
plants with equally small flowers. They do very well in pots
and are quite beautiful.
Angie Noack is a home and garden strategist
with a sharp edge for technology. With her unique ability to
combine these two skills, she's able to help gardeners save
time and increase productivity. You can find her online at

Add Beauty To Your Home With Climbing Roses

Angie Noack
Colorful climbing roses can add a dramatic effect to your home.
They're nice because you can wind them around a trellis, a
column, or even let them climb up the side of your home. It's
interesting to note, however, that many seasoned gardeners fear
climbing roses. This is likely because of the belief that
climbing roses can get damaged by cold weather and also because
they can take years to reach full maturity. Despite these facts,
there is a wide selection of climbing roses that can sustain
harsh weather.

The best time to plant any type of climbing rose is early
spring. Follow this advice and your roses will have about six
or seven months to become established before the cold sets in.
Before choosing climbing roses for your home, you should first
get acquainted with the three distinct categories of climbing
roses: ramblers, trailing roses, and true climbers.

The most intrusive climbing roses are the ramblers. These
exuberant roses can grow up to twenty feet in one season.
Although most of the roses from ramblers are quite small, many
of the newer varieties produce large roses. Unfortunately,
ramblers have a tendency to be susceptible to mildew.

If you're looking for a climbing rose that is tougher and less
prone to mildew and disease, your home might need the touch of
trailing roses. These climbers look great planted along walls.
It's suggested that you stake them because otherwise, the long
canes will grow along the ground instead of upright. Trailing
roses typically bloom approximately two to three inches in
diameter. Two of the more popular trailing roses are the
cultivars and Rosa Wichurana.

If you enjoy climbing roses with large flowers, true climbers
may be what you're looking for. These types of roses produce
flowers in large clusters. There are two categories of true
climbers: bush climbers, and climbing hybrid teas. Bush
climbers will continue to bloom throughout the season, while
climbing hybrid teas may only last for a few weeks out of the
season. The bush climber has more resistance to mildew and
disease than the climbing hybrid teas.

Planting your roses is an easy task. The first thing you'll
need to do is choose an area to dig a hole. Your hole should be
approximately one foot from your trellis or arch. Once you've
dug a hole, you'll also need organic matter. Well-rotted manure
or compost should be added to the soil. Next, carefully remove
the rose from its container. If you come across tangled outer
roots, gently untangle them with your fingers. Place your plant
in the hole and fill it in with any extra soil. Water it
thoroughly once you've planted it.

You should water your climbing roses at least once a week. The
soil should be saturated. Once your rose's canes have grown
long enough to reach the trellis or arch, tie the canes to the
structure. Unlike a vine, which is equipped with tendrils,
climbing roses have to be attached to a structure. You can tie
them with a soft cloth or string. The idea is to give the canes
enough room for growth and expansion. Be sure not to tie them
too tightly.

Choose the right roses for your home and watch them climb for
years to come!