University of Vermont Extension 
Department of Plant and Soil Science

Spring News Article


Charlie Nardozzi, Horticulturist and
Leonard Perry, UVM Extension Horticulturist
Potting summer bulbs, deterring pets in the garden, and sowing peas are some of the gardening activities for this month.

Dahlias, cannas, and gladiolus are available now and you can get a head start by potting them up indoors. Plant them in large containers and keep them in a cool room, if possible, in a sunny window until planting time outside. Dahlias may need to be pinched back while still indoors to keep the plants from getting leggy. You'll get earlier blooms with this technique.

If you have pets or neighbor cats and dogs that like to visit your gardens, take steps now to deter them. There are products you can sprinkle around the beds that safely repel animals, low fences that you can set up around beds, and gadgets such as pointed plastic spikes you can lay in popular digging spots. Even some wire mesh laid on bare ground may be all that’s needed to keep cats from digging.  It's easier to deter bad habits than to break them.

Once the soil reaches 45 degrees (F) and is dried out enough to dig in, it's time to plant peas. Choose a location in full sun and orient the rows north-south to take full advantage of the sunlight. Turn over the soil with a garden fork, or rototill if it's a new bed. Soak the seeds for a few hours or overnight (no longer or they may rot), and dust the seeds with an inoculant of nitrogen-fixing bacteria to help the roots take in more nitrogen. Set up your trellis first, then plant the seeds 1 to 2 inches deep.  Sow beets, carrots, radishes, and spinach outside now too.

Since butterfly bushes bloom on new growth, the best time to prune is early spring before new growth begins. Cut off the old stalks to within a few inches of the ground with pruners, loppers, or a pruning saw -- whatever is needed. If you want a more compact plant, also pinch off the tips of the branches in early May. If you wait too long, you'll remove flower buds. 

Now that you can see which rose canes have blackened and died, you can cut them back to green wood. Make slanted cuts about 1/4-inch above an outward-facing bud. Also remove any crossing and spindly canes. If any of last-year's leaves are still clinging to the branches, pull them off and discard them in the trash in case they contain disease spores.

Now is a good time to dig and divide perennials if they’re too large, didn’t bloom well last year, or are hollow in the center of the clump. Dig up the clump, and use a sharp spade to create pie-shaped wedges. Replant these divisions in a full-sun location in well-drained soil, and water often to keep soil moderately moist. An even easier method is to divide the plant in half, removing one half to divide and replant, and leaving the other half.

It's a good idea to test your soil every few years to determine its nutrient status and pH (acidity/alkalinity). Your state Extension Service can provide a reasonably priced test, and along with the results you'll get recommendations for improving the soil. At the very least test the pH, which you can do yourself with an easy-to-use home kit. You can find them at garden centers. The proper soil pH is important for plant health, specifically the availability of nutrients.

Other gardening activities for this month include sowing many flowers and vegetables indoors, moving woody plants if needed, and cutting back perennials if you didn’t last fall.       
(Charlie Nardozzi is a nationally known horticulturist, author, gardening consultant, and garden coach; 

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