Every spring my husband and I go to local garden centers to buy a few plants to fill in the gaps in our garden and buy annuals for summer containers. Like many plant lovers, we always depart from our list as we discover and decide what we need. So our landscape often looks more like a botanical garden display of multiple specimen plants than fleshing out the purposeful but naturalistic garden design principles we prefer.
Joe Raboine, Vice President of Design at Oldcastle Apg in Atlanta, Georgia, says that instead of scattering multiple single shrubs throughout the garden, planting small groups of three, five or seven similar plants creates a more unified yet natural look. “When homeowners plant things as stand-alone elements, they lack interest and pattern,” he says.
“It’s a very simple change that immediately gives the landscape more presence and purpose,” Raboin says. He and other landscape designers around the country explain how the rule of threes works and when it doesn’t.
What is the rule of three?
Despite its name, the Rule of Threes is more of a guide than a hard and fast design principle and is often used in a variety of design trades such as interior design and landscape design. At Marcy Bonner, Senior Associate Richardson and Associates Landscape Architecture In Washington, DC, agree that groups of three are more natural and visually dynamic.
“In landscape design, it’s really the broad use of odd-numbered groups, or natural-looking groupings of plants, that is more important than the strict use of groups of three,” explains Bonner. In general, planting in odd-numbered groups of three or even helps to avoid symmetry and create a cluttered appearance. Nature in your backyard.
William Winicki, general manager of Hicks Landscapes Hicks Nursery in Westbury, New York, says the goal is to avoid precise, spaced and perfect lines. “Our brains naturally try to organize things in straight lines or grid patterns,” he says. He adds that breaking up lines and sheer spacing leads to a more relaxed design rather than a rigid one.
What are some examples of using the rule of threes in garden design?
Despite my impulse buys and plantings, I aim for plenty of odd numbers Groups of plants. For example, I planted six lavenders in the upper bed because of their size, but later added five to the lower bed. This gave the lavender field a row-like appearance but not symmetry. “Odd-numbered groups make it easier to sway plants,” says Winicki. If you increase the number to double digits, he says, you can “create small groups of plants that flow and lead the eye to the garden.”
Raboine gives simple examples of the rule of three in landscapes like “Three”. Hydrangea Or ornamental grass Planted in loose triangles or groups of three small ornamental trees that form a natural-looking grove.” Some of the best native and xeriscaped landscapes Include a striking trio of the same shrub throughout the rock garden, for example, but in the same general view.
You can achieve the same natural effect no matter what Garden style Mix plant height, texture, or flower colors together in small groups as long as you avoid symmetry and obvious patterns. Winicki says you can create a layered effect in it Garden Bed Design “Putting tall plants in the back and short plants like groundcovers in the front.” Bonner adds that smaller plants create a uniform natural look and balance “in a mass rather than strictly numbered.”
Does the rule of three only apply to plants?
“Grouping an odd number of containers or garden pots can also create a more natural and harmonious arrangement,” says Bonner. She adds that arranging them in groups of three with different heights adds visual interest. Reboin suggests repeating elements like stones or stepping stones “in groups of three along the pathway.” Large single features like Fountains work well as visual anchorsBut “repetition of small elements in groups of three or five can add rhythm to a landscape,” adds Bonner.
You can also use the rule of three to design a layout Hardscaping elements In your yard,” says Steve Corcoran Lawn Love in Austin, Texas. “It helps even when the three things you’re using aren’t exactly the same,” such as with hardscaping elements, he says. For example, a three-container group might include the same pot design and color but different heights or different plants inside. “Garden accents like trellises, lights or sculptures can also be placed in groups of three to add structure and balance without making the landscape feel too formal,” says Bonner.
When should you not use the rule of three?
Planting an odd number is not always the best solution. “Like most design principles, it can fall apart if used too literally,” says Raboin. For example, if you only plant shrubs or display containers in sets of three or five around your property, the randomness can become a pattern instead. Likewise, you don’t need to take the odd-number principle to extremes, for example, count 15 or 21 plants. “Once you get to more than 10 plants, the plants become more of a drift planting,” says Winicki. This reduces the natural effect.
Winicki adds that if you want to include something a Pollen plantPut him in a place where he can do that job best. Maybe you have vegetable garden And only one of each culinary herb is needed to supply your kitchen; Scatter them intermittently with your odd-numbered groups. “Finally, if your garden is very small, you may want to be careful about how many plants you plant in one area,” Winicki adds.
The best time to ditch the rule of threes is when you want a more formal and symmetrical look. “For example, if you want to flank Front entrances or walkways, Placing a tree or pot on each side often makes more sense because it frames the entry and creates balance,” says Bonner. For more formal spaces like a front door or walkway, “two matching elements often make more sense because they reinforce the symmetry,” says Raboin.
Final thoughts
Corcoran says the rule of three is a popular concept in design that isn’t going anywhere. “I would probably even argue that it’s particularly popular in landscape design right now, when there’s a tendency towards creating style trends and preferences. A yard that looks more naturalfree or whimsical.” In fact, Raboin points out a similar attitude toward him Biophilic design. “Nature rarely grows in perfect rows,” he says.
New gardeners, in particular, can use the Rule of Threes as a guide for selecting and placing plants as a garden design principle. Although planting multiples of shrubs can limit plant diversity to a point, it also means learning to care for fewer plant types. And there’s nothing stopping pollinators from interspersing some of our favorite annual flowers or natives. “At the end of the day, the goal isn’t really to follow a rule. It’s to create a landscape that feels balanced, natural and welcoming,” Raboin says.
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