Containers vs. Pots for your garden and landscape.

Planters by the front door at a private residence

Is it a pot or is it a container? Who knows? So, what is the difference between a pot and a container? Well, since you asked, mostly it is determined by size.  Pots are usually small and can be easily moved. Containers on the other hand are much larger, having a capacity of more than 3 gallons of soil or 12” diameter and larger in size. They can be moved,but with much more effort and some are so heavy that is it better to leave them in place year round.  Containers come in many shapes, materials and sizes and include planters, window boxes, very large pots, urns, bowls, planting boxes, jardinières, and planting troughs.

A formal urn by Haddonstone

Landscape Architects use containers in many different ways.  Much in the same way that furniture can set the style in a room a Landscape Architect can use containers can set the style in the garden. Containers can be used to create a colorful accent at a doorway, to create an edge to a garden or path, as a design element for a garden space, an enclosing element in the garden or at the edge of a terrace, or as a focal point in the garden. Containers are mostly thought of as a garden element but they can best used in much more practical ways. On roof decks and plazas over structures planters provide enough soil depth to grows trees, creating shade and attractive gardens in urban settings. Also, after 9/11 security in public spaces and at corporate facilities became a very serious concern. The design problem was how to provide a security barrier quickly and attractively. In many public parks and plazas, landscape architects used large concrete planters to create security barriers and to control traffic flow. Addressing the need for security without sacrificing the aesthetic or design of the spaces they were protecting.

Large metal containers separate spaces on this commercial roof deck. Creating separate areas and providing security

Various options are available for containers. They can be made of different materials including metal, concrete, glazed ceramic, cast stone, terracotta, fiberglass, plastic, or stone. Of course it is vital that the container fits within its surroundings and matches the style of the garden. Most planters come in a variety of color and have options for texture.  These should be carefully considered when selecting them to make sure it is appropriate for the space. The container should blend harmoniously with the other materials nearby on the project.

Planter boxes can create a sense of rythm and reinforce a geometric layout

The planter should also be sized appropriately to accommodate the plantings that are intended to go into it.  Most annuals need 12-18” of soil depth to grow and look good.  If you want to grow a tree in a planter you will need 24-42” of soil and 6-8’ diameter minimum.  Careful attention should be paid to the soil mix, drainage requirements and watering requirements for the planters.  Many large planters in commercial settings have irrigation systems built into them.  Having the right soil mix for your application is important to success of the plantings.  Consider adding a soil moisture retaining polymer to the soil to prevent it from drying out.  Rooftop and over structure applications will require lightweight soil mixes keep the weight down.

Planters can be used as part of a formal perennial bed as an accent or repeated to create rythm.

Containers can be arranged in groupings of similar color, size or material or as complimentary groupings of diverse assortment to make a statement. Additionally containers are can be used as a formal design element in garden or landscape, as a sculptural element, for traffic control, for plantings on roof tops or on terraces were in-ground plantings are not possible. Other uses for containers are to plant non-hardy fruit trees (like oranges, lemons, limes, etc.) that are summered outdoors and then are carried inside for the winter months in areas of the country where the trees are not winter hardy and also for larger landscape plants like specimen trees, fruit trees, evergreen shrubs or flowering shrubs that are looking for permanent homes above ground.

You could also make a container out of a found object or cast-off like an old metal bucket, wheel barrow or bathtub, anything left up to your imagination could be used. These sort of containers can create a whimsical tone in the garden.

Hardiness Zone Map Change

by David Verespy and Barbara Wilson

Those of us with gardens in Connecticut, especially along the sound, have always been on the edge of things warmer.  We dreamed of warmer weather plants such as camellias, sweet box, gold dust plant and crape myrtle in our coastal gardens. A few brave gardeners have planted these southern beauties in protected corners and gone to great lengths to protect their prized garden gems from winter’s cold fingers.  Now with warmer temperatures and winters moderating these garden beauties can be included in our plant palette.

Garden beauties such as the Camellias flower may now be included in your southern Connecticut garden palette.

The United States Department of Agriculture (USDA) just issued the latest Plant Hardiness Zone Map for the United States.  The revised map now shows some regions of Connecticut which used to be a Zone 6b are now a Zone 7a. This means that some of those Zone 7 plants that you have always desired growing will now survive in certain locations. Weather changes to the coastal areas now indicate that southerly portions of Fairfield and New Haven Counties are in Zone 7a.

Plants that are now able to be grown in parts of southern Connecticut and coveted by most gardeners when they visit their more southerly neighbors include: Some varieties of Crape Myrtle, some varieties of Camellias, Sweet box, Gold Dust Plant, Needle palm trees. Several notable perennials formerly were considered annuals can now be planted and expected to survive including Gunnera, cardoon, verbena some lilies and many others.  The most important things this means for designers and gardeners in our area is that our palette of plants to choose from has been greatly expanded.

Camelias which have always been a staple of the southern gardens, but just out reach of the Connecticut gardeners now are a viable choice.  A broad selection of camellias are hardy to Zone 7 can be planted and some cold hardy camellia varieties have now been developed that are considered hardy to USDA Zone 6 with protection. These include:  Camellia ‘April Remembered’, C. ‘April Kiss’, C. ‘April Tryst’,  C. ‘Pink Icicle’, C. ‘Polar Ice’, C. ‘Winter’s Joy’, C. ‘Winter’s Rose’, C. ‘Winter’s Snowman’ and C. ‘Winter’s Waterlily’.

Another staple of southern gardens is Crapemyrtle (Lagerstroemia indica).  There are many Crape myrtles hybrid that are mostly hardy to USDA Zone 7, but can be killed to the ground in severe winters. There are a few varieties that are root hardy to Zone 6 and can be treated as perennials. Lagerstroemia fauriei is known to be reliably hardy to USDA Zone 6, but avoid planting them on a south-facing wall where the winter sun might break their dormancy too early. Zone 6 hardy or root hardy Crapemyrtles include: Lagerstroemia indica ‘Burgundy Cotton’,  L. indica ‘Red Rocket’, L. indica ‘Tightwad’, L. indica ‘Becky’s Watermelon Red’, L. ‘Sarahs Favorite’  and L. fauriei cultivars – ‘Bashams Party Pink’, ‘Biloxi’, ‘Choctaw’, ‘Hopi’. The Fleming Filigrees cultivars are hardy to USDA Zone 4.

Another southern gem which may become a staple of southern Connecticut gardens are the Crapemyrtles.

Local microclimates can affect plant health and survivability in your area so be aware if your area tends to be colder or warmer than the norm indicated on the USDA Zone Map. Often properties near to lakes or ponds will have a more moderate air temperature and possibly a zone warmer, whereas if you are in a valley the cold air tends to settle so you may be a bit colder. Urban areas, because of the heat island effect of the mass of asphalt and buildings tend to make them a zone warmer than surrounding non-urban areas. Some areas with more consistent snow cover can consider planting species that are from a zone warmer, since the root zone is insulated during the winter months.

How will this affect your garden or landscape? Plants that are growing in your garden now have adapted to the seasons and the gradual changes in minimum temperatures of the region. You should not worry if they are growing or thriving now. Just make sure to continue to plant any new species that are tested and labeled for your hardiness zone.

Not sure what to plant or need help planning your garden. We can help you plan ahead to make your dream garden a reality, call Rock Spring Design Group, LLC at 203•268•6979 or email us at info@rockspringspringdesign.com today for a free one hour consultation to discuss your dreams garden. www.rockspringdesign.com

The USDA Zone Hardiness Map is available as an interactive tool online at www.planthardiness.ars.usda.gov. You are also able to find your zone by entering your zip code.

USDA Hardiness Zone Map for Connecticut
Temperatures Included in Each Zone

Zone 5: -29 to -23 C (-20 to -10 F)
Zone 6: -23 to -18 C (-10 to 0 F)
Zone 7: -18 to -12 C (0 to 10 F)

Hardiness Zone Map