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COLUMN: Gardening tips for May

The annual St. George's plant sale is June 3, in Clarksburg
JohnHethringtonDaffodils
John Hethrington with some daffodil's he's "dead-headed."

Master gardener John Hethrington works all year-round on his 20 gardens, but in the spring, the task list gets quite a bit longer.

Here are his tips for May gardening tasks:

If not done already, clean up winter debris in the garden as soon as the soil is dry enough to work. Cut off dead plant stocks. Dig in manure or compost around perennials and shrubs and weed well. An extra hour of weeding now, will save three days later in the summer!

Use a line to cut sharp straight edges for your beds. For curved edges, run hot water through a hose to soften it up and lay out a smooth curve. Watch you don’t chop the hose!

Take pictures of your spring bulbs in each of your gardens so you will know where there are any gaps and where the bulbs are when you plant more bulbs in the fall. Save the pictures in a safe place. 

Plan now to plant early blooming bulbs like snowdrops and crocus in the fall at places close to where you come in and out of the house. It’s nice to be greeted by early signs of spring.  

Add three-to-four inches of mulch to flowerbeds and shrubs to conserve moisture and discourage weeds. Shredded cedar bark is best, but expensive.

Don’t walk on or roll lawns that are still wet and full of water. If you can see your footprint, stay off the lawn. It will compact the soil.

If your lawn is already compacted, rent an aerator which will dig out small plugs. Let the plugs dry and rake them back into the lawn as a top dressing. Add grass seed to bare patches.

When dry, rake lawns vigorously to remove dead grass and thatch.

Spread weed-free topsoil on thin patches in your lawn. Apply grass seed, roll and water. Keep seeded areas moist, but don’t flood.

If you find moss in your lawn, the soil is too acidic. Apply dolomite lime before rain. You may need a second application. 

If you have pots or planters that are very big or deep, put some empty plastic water bottles with lids in the bottom of the pot to take up the space the roots will never get to. It makes the planter or pot lighter and easier to move.

Prepare containers and pots for planting. Fill with a mixture of compost and potting soil. Add peat moss or better still, coconut coir to retain moisture.

Place pots with culinary herbs close to the kitchen door for easy access.

Harden-off seedlings for at least a week before planting outside. Google the last frost date for your area (June 1 in the Blue Mountains) and allow at least one week more before planting tender transplants such as annuals and tomatoes.

Walk around your garden and look for perennials that should be divided, are in the wrong place, or you don’t like any more. Pot them up for spring plant sales at least three weeks before the sale. Add compost, not garden soil to the pots. To be really fancy, add a little bone meal to the pot before you put in the plant. Add plant labels with the name (botanical and/or common), colour, sun exposure, height, bloom time, etc. Water well and keep in the shade.

Pot up and donate 15 or more perennials to the St. George’s annual plant sale and get an income tax receipt for the retail value your plants sell for. Bring them to the church Wed., May 31 from 9 a.m. to 3 p.m. It’s a win-win for everyone. 

The giant annual St. George’s Plant Sale is Sat., June 3, this year on the church grounds in Clarksburg. It starts at 8 a.m.

Plant beans now directly into the garden as they germinate quickly and will grow as long as the soil is warm. Maybe mid-May this year.

Install peony rings before the plants start to grow.

Monitor for the presence of slugs, cutworms, earwigs and tent caterpillars. Pick them off.

Control weeds in the lawn by hand pulling. Use nematodes to control grubs, which eat the grass roots, leading to brown patches in the lawn in summer.

Prune roses according to type. 

Deadhead (cut the blooms off) tulips, daffodils and other spring bulbs but do not cut or pull out the leaves until they are brown and decayed. They are needed to nourish the bulbs for next year’s bloom.

If you have any fritillaria or Asian lilies (day lilies are beetle free), now is the time to watch for the red lily beetle (adult, larva and eggs). It seems that removal by hand is the best and only way to reduce this problem.