How to get the best color in your garden

Color is a powerful problem-solver. It can overcome a bad location. Vivid hues will insert personality into bland architecture. Color is so potent a tool that even the most problematic landscape can be salvaged with enough of it.When color goes to work, it becomes the driving force of a garden. As a problem solver it must be bold and laid out with a generous hand to function as desired. But at the height of spring bloom season, you'll notice some homes with flowers fail to wow us. This is because those folks have not followed the simple yet essential rules of color gardening.First of all, the color must be dense and pure. This means that flowering plants must be spaced so that they are visually one continuous mass of color. When there's bare ground separating the plants, they read as singles, not a mass. It's unavoidable when they're young, but after a short time they should fill in edge to edge. Problem is, they don't always reach this optimal size.Professional bedding-plant designers know that they have to push the limits of these plants to get the eye-popping looks they're after. If a plant should ideally be given 1 square foot of space, the designer will stipulate less than that to get them packed in tightly in the field. No, it's not ideal for the health of the plant, and you'll have to provide them with plenty of fertilizer to keep every one blooming, but that's just how it's done.Planting larger masses of each color makes them read. The novice is more often than not going to put a few of this color here and a few of that color there, without much consideration for how large or floriferous they'll be at maturity. This spotty look will result in a mixture that fails to read at all, and just doesn't do justice to the beauty of each color variety.Plan larger masses of each color, and if you stick with just two or three, these masses will surprise you with their visual assertiveness. The masses should drift in naturalistic forms rather than blocks or circles, which is our human way of arranging them. But you'll never see blocks or circles of wildflowers because nature is far more random. Drifts become the cultivated version of nature's random planting, which is indeed not random at all.A color planting with just one plant height is technically "carpet bedding," which went out with the Victorians. Today's gardens demand more visual interest, because the variation in form on top of intense color is what makes a planting sing. The tendency is to stick with flowers of the same height such as lobelia and violas and dwarf French marigolds. This is commonplace and rather institutional-looking.When you select plants for color drifts, seek to blend tall spikes such as foxgloves or medium-height blue salvias to create vertical elements. These verticals give you welcome relief to the ground plane, and their location helps define the space where shorter plants will be arranged. They are your most powerful design tool, which may change each year as you reinvent your color planting.Medium-sized plants such as stocks, red salvia, African marigolds and marguerites offer more spreading forms that cover larger areas with big bold color swaths. These will drift around the taller plants like ripples in a pond or the raked patterns in zen gardens that flow around large boulders.If your spring garden doesn't light your fire, perhaps you've failed at one of these three essentials. The solution may be as simple as filling in the gaps, adding more of each color or inserting a cluster of spiky growers to provide welcome summer relief.(Maureen Gilmer is a horticulturist and host of "Weekend Gardening" on DIY Network. Contact her at her Web site www.moplants.com or visit www.diynetwork.com. For more stories, visit scrippsnews.com.)