University of Vermont Extension 
Department of Plant and Soil Science

Spring News Article
Charlie Nardozzi, Horticulturist and
Leonard Perry, UVM Extension Horticulturist
Sowing arugula and other greens, spraying horticultural oil on fruit trees, and trimming back ornamental grasses are some of the gardening activities for this month.

To get an early harvest of arugula and other greens, dig out a large shallow container and sow some seeds. Grow them indoors until the weather warms enough to put them outside during the day. Keep cutting leaves from the outside of the plants to prolong the harvest. Or you can sow seeds for a mesclun mix and cut off the leaves when still young. They will regrow for another harvest in a few weeks.  Look for seeds to sow and grow quickly just for sprouts.

Warm days may tempt you into removing winter mulch but wait a bit longer. We still could have snow and some very cold nights, and plants still need protection. The freeze and thaw cycles of early spring can damage plants that have survived a cold winter.

Spray horticultural oil on fruit trees, such as apples, plums, and cherries, to smother any overwintering insects. Choose a calm day when temperatures are above 40 degrees (F), and be sure to cover all sides of the branches. You also can apply it to evergreens to control spider mites and other insects. Carefully follow the instructions on the label for proper usage and appropriate plants.     

Remove the old stalks from ornamental grasses before new growth begins or you'll cut off new growth when you prune. For large plants, you may need to use hedge trimmers or a pruning saw.  Also, don’t cut too low or you may remove this year’s growing points.  Cut to at least 6 inches (12 inches or more is best), above the crown.  It may help to tie the stalks of larger plants together before you cut.  If possible, chop the stalks before adding them to the compost pile or using them as mulch so they will decompose more quickly.

Suckers that sprout from the base of crabapple trees and other fruiting trees will rob the trees of energy needed to form fruit, so don't let them grow unchecked. Pull them off if possible because this reduces their regrowth more than cutting them, but use whatever method you need to remove them.

Wait to start seeds of tomato plants until next month.  A common mistake is to sow them indoors too early, resulting in leggy plants by the time they can be set outside in May.  You should start seeds of cole crops (broccoli, cabbage and the like) indoors now.  Sow slow-growing flowers such as pansies, begonias, and vinca early in the month.  Sow verbena, petunias, geranium, and impatiens later in the month.

Unless you have a sunny window much of the day, adding grow lights over seedlings will help.  These can be turned on (a timer such as you find at hardware stores is very convenient) during the darker parts of day or evening, to give plants 12 to 16 hours of good light a day. 

Other activities for this month include starting begonia tubers, cutting branches of early-flowering shrubs (such as pussy willow and forsythia) for forcing indoors, taking your mower in for a tune-up, attending flower shows and gardening seminars, and visiting a maple sugarhouse.
(Charlie Nardozzi is a nationally known horticulturist, author, gardening consultant, and garden coach; 

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