This time of the year, as the chance of a late frost diminishes, greenhouses and plant sales are crawling with enthusiastic gardeners.
While finding the right plant is paramount, it’s also important to find a healthy plant. After all, if you’re going to spend money and time to nurture your purchase, you’ll want a robust plant that will thrive through the season.
Robert Cox, a Colorado State University Cooperative Extension horticulturist in Jefferson County, offers these tips for choosing healthy plants.
Small or tall: Look for a bedding plant that is short and stocky, not tall and skinny. The stocky plant has been given plenty of light and good air movement.
Flowers or not: It’s tempting to buy a plant with the most flowers. Blooms offer a peek at what the plant will look like, but, says Cox, restrain yourself and instead buy plants with few or no flowers. Instead, choose ones that have buds.
Plants without blooms throw their energy into developing roots, which is most important for vigorous growth later. “Some people even pinch off the blooms,” says Cox. The act is counterintuitive, but blooms will return in a few weeks. And in many cases, the shock of transplanting may kill off blooms anyway.
Overall look: The plant should look healthy. Most plants should have several stems, not just one. Leaves should be green, not yellowing or brown, rolled-under or blotchy.
Yellowing or browning could be a sign of under- or overwatering. Blotchy or disfigured leaves might mean the plant has a disease or is infested with insects.
“Greenhouses take care not to sell diseased plants,” says Cox, “so you probably don’t have to worry too much about that.”
Roots: Roots should be white and creamy-looking, not brown or black and mushy. Avoid root-
bound plants. If all you see is roots and no dirt, then the plant is root-bound in its container. Greenhouse owners might not appreciate customers who pull plants out of their cells for a peek, so if you have a concern about a certain plant, either ask for permission or check out the bottom of the pot. If no or few roots are growing out of the drainage holes, then the plant still has room to grow. Roots should not show above the soil surface.
“Sometimes, when the plants are so root-bound, they refuse to grow out into the surrounding soil,” says Cox. This especially happens with plants in six-packs.
To prevent that, simply make two or three cuts with a knife blade through the roots or loosen the roots and soil with your fingers before planting.
Labels: While plant tags don’t always offer a wealth of information, what they do tell is important. Don’t plant a shade plant in full sun or vice-versa and wonder why it didn’t grow. Pay attention to how far apart plants, especially perennials, should be placed in the ground.
“People like to cheat, but they don’t look down the road to see how crowded things will be,” says Cox. If the label says plant 12 inches apart, don’t place them in the ground any closer than 9 inches apart for a quick fill-in. Use annuals for that purpose.
Container size: There’s nothing wrong with smaller plants and they are easier on the wallet, says Cox. However, if purchasing cool-season vegetables, such as broccoli, pick a larger plant to go into the ground since it already is fairly late in the season.
Once purchases have been made, make sure to harden off the plants before you place them in the ground. Cox suggests placing the plants outside for a few days, then allow them to spend the nights outdoors before placing them in the ground.
“Outdoors Colorado is so different in a garden than at a greenhouse,” says Cox. And, he adds, never place plants directly into the soil. Plants need an adjustment period or they could die or be harmed by the transplant process.
