top of page

Talkin' Dirt - May 2016

by Mary Beth Riggs

The month of May is a time when the weather can either turn your garden into an Eden, or a wasteland. Be aware of the weather forecasts, trends and warnings.


Hardiness zone maps are based on past years’ averages, and can't predict a freak frost or snowstorm, or a prolonged spring drought.

If a frost or cold weather is in the forecast, protect your tender plants with a mulch, newspapers, light cloth or some type of overnight protection.  A frost cap can be made with a roll of poly film tented over the plants. Be sure to remove the plastic tent as soon as the danger of frost is over so your plants won’t bake in the sun.


If the weather is sunny and dry, don't neglect your watering!  Most flowers and shrubs need about an inch of water each week to perform well, and newly planted seedlings especially, will perish if their roots are allowed to dry out.


May is also a time of gardening inspirations and dreams.


Look around yourself and notice what your neighbors are growing in their gardens and what they are creating in their landscapes. Think of how you might utilize some of their ideas along with your own brainstorms to make your garden just a little bit better.


Weeds, Weeds, Weeds and more Weeds


Keep after weeds while they're small -- they're easier to pull and if you get them before they go to seed, you won't have as many weeds to pull next year.


Pull weeds after spring rains, and they'll slip easily from soil rather than when the ground is dry.


Deal with weeds in driveways or along paths with spot sprays of glyphosate -- or for a more environmentally friendly solution, try boiling water.

Vinegar kills young seedlings, but is ineffective on older growth. Vinegar damages any plant surface it touches. Use with caution on windy days.


Garden Tip: Insert stakes for flop-prone perennials when plants are 6 inches high. Candidates include peony, heliopsis, summer garden phlox, or Shasta daisies. Plants will hide stakes as they grow.


Caring for Your Shrubs and Trees - It's still not too late to fertilize


Use a rhododendron or evergreen type of plant food to feed evergreens and other acid loving plants like Azaleas and Rhododendrons, Camellias and Junipers, etc. Use an all-purpose garden fertilizer (10-10-10) to feed roses, deciduous shrubs and trees.
Be sure to water in the fertilizer  thoroughly after it is applied.


Early flowering deciduous shrubs such as Forsythias, Weigela, and Spirea should be pruned back when they have finished blooming. Cut back a third of the oldest canes to ground level, then cut back one third of the remaining branches by one third of their height.

Remove the wilting seed heads from Rhododendrons and Azaleas so that the plants energy can go to foliage growth and next year’s flowers, rather than seeds.


Work lime in the soil around your Hydrangeas to produce pink flowers or Aluminum Sulphate for blue blooms.

Remove any sucker growths from fruit trees as soon as they appear!


Keep a vigilante eye on the roses.   Keep them sprayed for aphids and other pests and diseases such as black spot.

Pines and other conifers can be kept to a compact size by pinching off the new growth 'candles'.


Lilacs should be pruned lightly after they finish blooming, removing sucker growths and dead blooms.  Feed lilacs in May with a good all purpose 10-10-10 fertilizer after they have finished blooming.  If your soil is acidic, work a little lime into the soil as well.


Caring for your Annuals, Perennials and Bulbs


Dahlias, gladiolus, Lilies, Cannas and other summer flowering bulbs can be planted this month.  Gladiolus bulbs may be planted at 2 week increments until the first of July to provide you with cut flowers until the first frost.


Delphiniums, phlox, daylilies, carnations, Aubrietia, candytuft, Basket of Gold, primroses, coral bells and other summer flowering perennials may all be set into the garden any time in May.


Break off wilting tulip or daffodil heads but continue to feed and care for the plants until the foliage has died back naturally. Old plantings of daffodils may be divided and moved when they have finished blooming, but treat them as growing plants and use care to protect the foliage and roots.
Water them thoroughly after transplanting.  It is best not to dig or move other spring flowering bulbs until their foliage has ripened and died back.


Pansies, snapdragons, dianthus, petunias, geraniums, fuchsias and impatiens should be ready to plant by mid month. Toward the end of the month, it should be warm enough to plant the more tender annuals like salvia, zinnias, marigolds and Cardinal flowers.


Lightly side dress perennials with an all-purpose 5-10-10 or 10-10-10 fertilizer. Avoid spilling the fertilizer on the plant, and use care not to damage the shallow roots when you cultivate it into the soil.


Promptly remove spent flowers from any plant unless your intent is to harvest the seeds. It consumes the plants energy to produce the seeds, and in many species of plants, especially annual plants, removing the dead flowers will promote further blooms.


Gardening Odds and Ends


Slugs and snails are out in full force right now.. and they are ravenous! Be sure to take steps to control them now, before they have a chance to reproduce and devastate your garden.


If the weather refuses to cooperate with your gardening plans, and your seeds have refused to germinate due to cold and wet conditions, you may want to consider replanting a reserve crop (Just in case....)


The compost pile should be getting a lot of use these days, both in utilizing this free fertilizer, and adding fresh garden refuse to it. The compost pile should be kept damp. Frequent turning will turn your garden waste into flower food much faster.


Top Deer-Resistant Plants of the Northeast

If deer treat your yard like a buffet line, try these plants. But keep in mind that deer in your neighborhood may have already developed a taste for some of these plants. Unfortunately, deer do not read lists.


To start, we need to set a ground rule: There aren't really any plants you can truly say are deer proof. And the animals are smart and unpredictable -- so the deer in your yard may love a particular plant, but avoid it in a garden down the block.


Check out these plants as a great starting point to creating a garden in which the deer won't frequently dine:


Bee Balm



Golden Marguerite


Japanese Painted Fern

Lily-of-the Valley


Meadow Rue

Sea Holly

Sweet Woodruff


Wild Ginger


Herb Gardening


Tuck herbs into the garden as soil warms.

Plant dill and fennel in vegetable gardens and flower borders for an airy texture. The blooms  attract beneficial insects, which can keep harmful insects in check. Allow plants to set seed and you'll be rewarded with volunteers next year.

Edge your planting beds with herbs. Chives, 'Spicy Globe' basil, tricolor sage, and parsley all make pretty edgings. Thyme forms a lovely ground-hugging mat that's ideal for front-of-the-border planting.

If your planting beds tend toward the moist side, tuck Mediterranean herbs -- rosemary, thyme, and lavender -- in unglazed terra-cotta containers. The porous pots keep roots on the dry side, so plants can thrive.


Happy Gardening!!!

Mary Beth



bottom of page