May: To Do in the Garden

By Gary Crispell, EMGV

Just another confused spring.  Our April showers all came in March and the winds of March have persisted throughout April not to mention the late frosts.  Sheeesh!  And May??  Who knows?  Might be July hot or April cool or all of the above.  Guess we’ll have to wait and see.  There don’t seem to be any gopher prognosticators for the spring/summer interface.

At least the Accidental Cottage Garden appears to have escaped serious damage (mostly).  The peonies (Paeonia officinalis) are spectacular as are the white with purple fringe iris (Iris x hybrid).  I used to know their name, but I can’t remember anybody’s name anymore, so it’s the “Hey, you” iris.  They are joined by two clumps of dianthus (Dianthus ‘Sweetie Pie’) and the little orange flowered plant.  $100 (in Monopoly money) for an ID of it. 

(Left to right) The Accidental Cottage Garden comes to life featuring Dianthus ‘Sweetie Pie’, iris, peonies (Paeonia officinalis), and a mystery plant with orange blooms despite unpredictable spring weather. (Photos by G. Crispell )

I suppose you really came to this for a gardening calendar, like it says at the top.  If you insist.


Do you have a cool season lawn (Fescue or Bluegrass)?  Recent research has indicated that fertilizing after mid-March will not cause a cataclysmic decline of your turf grass.  The use of a balanced fertilizer (10-10-10 or equivalent) be used as opposed to a high nitrogen slow-release variety.

For those of us with warm season lawns (Bermuda, Zoysia) now is definitely the time to put out a high nitrogen (the first number on the bag) slow-release fertilizer.  Y’all with centipede lawns would do well to wait until late May or early June to make a similar application.

Mow cool-season grass at 3”-4” and warm-season at 1 ½” to 2”.

FERTILIZING (other than grass)

Crops that take all season to produce or those that produce all season (subtle difference in wording—big difference in crop) would be most delighted with a feeding of a balanced fertilizer about now.  Same goes for your annuals that will reward you with prodigious quantities of blooms.

Acid loving (ericaceous) plants (E.g. azaleas, other rhododendrons, camellias)  can be fed with an appropriate amount of acidic fertilizer.  (You know the appropriate amount because you got a FREE SOIL TEST earlier).


For ideal veggie planting times check out the NCSU website’s Central NC Planting Calendar for Annual Vegetables (see link in resources section below). The site is very helpful and includes flowers plus when, how, and how far apart to plant all things annual.


Grab those shears and loppers (the ones you sharpened and oiled in December) and put ‘em to work.  Any of your spring flowering plants that need pruning should be pruned very shortly after they finish blooming.  Many of them set next year’s buds within six to eight weeks of blooming.  Pruning procrastination will have a deleterious effect on next year’s floral display.

Check azaleas and camellias for leaf gall.  It doesn’t harm the plants, but it ain’t purty to look at.  Just prune out the galls as necessary.

Keep garden mums (Chrysanthemums spp.) pinched until mid-July if your intent is a Fall bloom time.

I know your grandmother always cut off the foliage of her spring bulbs right after they finished blooming.  Don’t.  Just don’t.  The leaves produce sugars (that’s what photosynthesis does) that feed the bulbs so that they can produce flowers next year.  Wait until the leaves turn yellow before cutting them. 


To prevent borers on iris, rhododendrons, blueberries (Vaccinium spp.) and squashes apply a properly labeled insecticide now.

Spray fungicide on all of your fruit trees & bunch grapes and any tomatoes that show signs of early blight.

Keep on keepin’ on with any rose programs.

Check trees and shrubs (especially evergreens) for bagworms.  They are out and about this month as none of them has ever had the foresight to make a bag big enough to mate in.

Many vining undesirables are more susceptible to herbicide application right now while they are actively growing.  Think poison ivy/oak (Toxicodendron radicans/T. toxicarium), honeysuckle (Lonicera japonica), English ivy (Hedera helix), etc.


Replace your pansies (Viola hybrids) with summer annuals.  The pansies may still look decent, but as soon as it gets hot and stays that way they will whither and perish.  Can’t take the heat and no way to get to the mountains.

Take those house plants outside and feed them.  They will appreciate the outdoor vacation and the meal.  Just don’t set them immediately in the direct sun.  Let them get used to the light by setting them in a semi-shady spot for a few days.  Coppertone doesn’t work real well on houseplants.  They do not take to it kindly.

Pollen season should be over now.  Wash the deck/patio furniture, raise the umbrella, pour a good cool beverage and sit down and enjoy the fruits of your labors. 

*Resources and Further Reading

NC Extension’s Carolina Lawns: A Guide to Maintaining Quality Turf in the Landscape

NC Extension Gardener Handbook – Herbaceous Ornamentals (learn about choosing annual and perennial plants, care, fertilization, and garden design)

NCSU’s Central NC Planting Calendar for Annual Vegetables, Fruits and Herbs


Vegetable Gardening: A Beginner’s Guide

General Pruning Techniques for Trees and Shrubs

Article Short URL: