Garden Notes : March, March, March, June
The coolness and lateness of spring this year reminds me of typical weather patterns from before 15 or 20 years ago, when we started to experience early, bizarrely warm spells. Older people I know use the forsythia bloom as their own phenological sign to start planting in their gardens; it usually happened mid-month, just as it has in 2009. Even sunny days retained a chilling bite to the air that could be felt, except in the most sheltered spots. All of which amounts to: things are later this year and we can expect a more compressed "March, March, March, June."
Make successive plantings of Swiss chard, spinach, cilantro, and lettuce. Start green beans and sunflowers in cells indoors. Hardening off outdoors is tricky; seedlings sunburn easily. Check out COMSOG's plant sales.
In ornamental beds, the biggest job is cutting back and cleaning up. Gardens left in a tidy state late last fall, probably have had debris blown into them, especially fluffy matter like last year's flowerheads of hydrangea and ornamental grass. A note on deadheading hydrangeas: in our climate the flowerheads are left on all winter to provide some protection from winterkill to the buds, which contain flowers for the current season. The same applies to buddleia and other plants that fall midway between herbaceous perennials and woody shrubs, whose leafbuds would be destroyed over winter without the protection of the old wood.
Reliable standbys in Island gardens include buddleia, caryopteris, potentilla, nepeta, and Montauk daisies (Chrysanthemum nipponicum.) All need cutting back and/or a cleanup in spring. It can be done safely now. Cut buddleia and Montauk daisies back pretty hard to achieve a stockier, more floriferous plant. We usually pinch the Montauks once or maybe twice more before we leave them alone sometime in June to develop their flowerbuds.
Stands of Rosa rugosa and its hybrids, like "Sir Thomas Lipton," can be cut back now. Look for outward facing buds 12 to 14 inches from the soil line and cut the prickly stems just above. New vigorous sprouts that are stockier and lean less will grow. Apply a dressing of compost, organic fertilizer, or well-rotted manure.