Eastern Iowa plant sales and garden centers are in full swing, offering gardeners lots of choices for bedding plants, vegetables, flowers and perennials. Some of us also have houseplants that soon will be going outside. But after a weekend of hitting local plant sales, it’s best to take some time to acclimate your new plants to outdoor conditions. Many of these plants are grown in greenhouse conditions that are much less harsh than our backyards.
Sudden changes in light levels, moisture and air movement can shock plants, dry them out or even break them on a windy day. Temperature extremes also can slow growth particularly in warm season plants such as tomatoes, peppers and squash.
Acclimating newly purchased plants to the outdoors is called hardening off or transitioning. This allows the plant’s tissue to handle all the weather that an Iowa spring dishes out. So how to do this?
Place plants outdoors in a bright location, but not in direct sunlight for a couple of days. Gradually move those plants into full sun for a few hours at a time. Extending their exposure to full sun by an hour or so each day. This is particularly important with houseplants that are going outside.
Make sure you check new bedding plants outside for water. Six-packs of annuals can dry out very fast.
Protect plants from wind. Newly purchased plants can be damaged easily. If you have plants that are particularly tall, stake them to prevent stems from breaking. It’s also a good idea to protect newly planted bedding plants and containers from heavy rain. If strong storms are in the forecast, set your pots in the garage or under a structure for protection. Perennials can handle more weather, but they also can be protected by placing an upside down flower pot on top.
If a late frost is predicted, most perennials will handle it but bedding plants and warm weather vegetables will not. If they are in pots, bring them into the garage, if not, cover them outside.
If you haven’t yet been plant shopping, you’re not too late. Many area plant sales are coming up including the Linn County Master Gardeners plant sale at 8 a.m. Saturday in the Iowa State University Extension parking lot at 383 Collins Rd. NE, Cedar Rapids. You’ll find a wide variety of healthy and vibrant annuals, perennials and houseplants at bargain prices. Many of these plants are from Master Gardeners’ gardens, including hosta, day lilies, wildflowers, ground covers, ornamental grasses and other perennials. The sale also features vegetables, herbs and annuals grown. Master Gardeners will be on hand to assist you with plant selection and answer any questions you may have about proper care for newly purchased plants.
Lisa Slattery is a Linn County Master Gardener.