Preparing for the planting season

Planting in late spring and summer subjects plants to their own form of jet lag. But with plants, it’s a seasonal thing, not a night and day thing. During these fecund months, container plants are growing, flowering and fruiting vigorously. They need every ounce of energy to pull off these functions. But when transplanted just before the onslaught of summer heat into your garden, they’re too busy growing to sleep off the change. Like that business traveler, they have to get used to a new location while performing a plant’s version of a full meeting and seminar schedule.

Plus, there’s an added demand when days are very long, temperatures high and water supplies intermittent. No wonder June-planted shrubs, trees and perennials look so weak that first year. They’re just trying to cope with a normally heavy work load on top of jet lag in a trying new environment. The remedy for botanical jet lag is to plant in the fall. Yes, this forces us to step outside our primal springtime planting urges. It can be downright difficult at summer’s end to start planting when you’re ready to sit by the fire or get the kids off to school. Just imagine how your new plant would perform in the first year if granted six months of resting time before it had to sprout leaves and flowers. It would be just like giving every business traveler a week off to adjust to the new time zone before the onslaught of work.

Fall is considered the very best time to plant. Days are growing incrementally shorter, signaling plants to slow leaf, stem and flower development. This forces energy into a growing root system. Soil temperature is moderate and rainfall softens the ground so new roots may venture well outside the container shape.

In the West and other arid zones, planting in fall is even more essential. The intense heat of summer is accompanied by very low humidity levels. If the new plant has not developed a sizable root system, it will have a hard time surviving under these conditions. But a plant that’s been growing roots all winter will have invaded a much larger soil mass, particularly deeper down where moisture does not suffer surface evaporation. It will be far less vulnerable than a new spring transplant.

Shopping for fall color trees while they’re turning helps to choose a good performer. In warmer climates where autumn hues don’t always appear, this is the best way to find a stellar liquidambar. With species such as seedling Japanese maple that can vary in late season intensity, buying now guarantees great color.

Fall planting also helps you get a head start on the spring garden. Plant spring bulbs to add interest in mixed beds and borders for early spring. Crocus will be a most welcome color at winter’s end. You also can sow seeds of over-wintering annuals, such as coreopsis, hollyhock, larkspur, poppy and sweet William.

The business traveler and the ardent globe-trotting tourist both know how much jet lag can cut into your time in a far away place. But if we can’t get the boss to give us time to acclimate before the onslaught of work, it’s the least we can do for our plants.

Maureen Gilmer is a horticulturist and host of “Weekend Gardening” on DIY Network. Contact her at www.moplants.com.