While planting annuals yearly can be fun and adds a bit of variety to your landscaping, many prefer to build their landscaping and flower beds around perennials, because of their ease in seemingly “automatic” yearly recurrence, without much work or care. Taking care to select perennials right for our growing zones and existing shade conditions, with just the right heights, colors and timing of blooms, we wonder when to plant them.
Realistically, seasonal flowers can be planted at any time of year. Most can be planted even before annuals, when the spring air temperature is still cool and rain is plentiful. However, there is some discrepancy as to what is “best.” For instance, it is recommended that larger perennials be planted in the fall, as the cooler air reduces stress on the tops of the plants but the soil remains warm enough for the roots to become established. These plants should be mulched and the tops cut back when the ground freezes. Ideally, when spring arrives, these plants will be ready to burst awake. The exception is larger plants that are late bloomers; these should be planted in the spring. If you feel uncertain, consult with your local landscaping professional.
Unlike the larger plants, smaller perennials may not be able to root deeply enough to withstand the rigors of winter if they are not planted until fall. Therefore, such smaller perennials should be planted in the spring. Springtime is really the preferable time for planning most perennials. Sit your perennials in good soil, making a kind of basin for them. Mulch should be applied around each plant and they should be given a good watering after planting. Never plant perennials in waterlogged ground; too much water keeps oxygen from getting to the roots.