Meet Mark Cullen

Canada's best known gardening personality, Mark Cullen believes that Canadians of all ages need to play more - preferably in the dirt. A best-selling author with over 400,000 books in print, Mark reaches over one million Canadians every week through various media outlets. He is Home Hardware's horticultural spokesperson and regularly contributes to various magazines, gardening shows and newsletters. With a familiar style that people can relate to, he delivers a message that is compelling, fun, informative and inspirational - all based on his organic approach to gardening. In his spare time Mark enjoys driving his Ford Model A - and of course he loves to garden.

The Trouble with Impatiens

~ October 26, 2011

Did you plant impatiens this year? Did they dieback mid-season leaving you disappointed? Well, you are not alone. I have heard from many gardeners who experienced the same puzzling results.

According to Horticulture Review, there is no clear explanation for this problem. One contributor blamed the large amount of rain early in the season, which caused fungus in the soil. This was followed by extreme heat and dry conditions.

Horticulture Review contacted scientists for answers:
Shannon Shan at the University of Guelph’s Pest Diagnostic Clinic received a few samples with a couple of root and crown rot pathogens showing up after culturing them. Shan’s thoughts are that perhaps the cool wet spring provided the perfect growing conditions for Rhizoctonia, a crown rot, and that gardeners should be using crop rotation with ornamentals – just like we do with vegetable crops.

OMAFRA specialist Wayne Brown looked at photos of dead impatiens. He said, “It is very difficult from the photos to say with any degree of certainty the cause of the defoliation. In the one instance, it looks like it might have been caused by Rhizoctonia, because the basal stems looked blackened, but Rhizoctonia does not typically cause defoliation. The defoliation is more consistent with either Alternaria Leaf Spot or downy mildew, but I can’t confirm based on the photos which of the two disease pathogens it might be.

Brown added that watering the plants during the night, or very early morning would promote development of either disease, and also recommended planting something other than impatiens next year to allow over-wintering inoculum to diminish.

Michael Celetti, a plant pathologist with OMAFRA, thought the problem might be Pythium, a water mold, causing root rot. Celetti notes that Pythium can be managed in the greenhouse, but once the plants are installed in the landscape it is difficult to control as it is spread by water. To help control Pythium, it is better to water lightly and frequently – which goes against the usual recommended practice of irrigating infrequently and deeply.

While there is no clear answer at this point, it is comforting to know I was not the only gardener whose impatiens packed it in early this year. I plan to rotate my annual plants to new locations next year and hope for better results.

(Source: Horticulture Review – October, 2011)

Your Fall To-Do List (Part 2)

~ October 19, 2011

The deadline that we have before us today is winter. We can go south to escape the cold and wind but your garden does not have that option.

It is with this in mind that I continue my comprehensive to-do list from last week’s blog.


• Pull up your remaining tomato plants and hang them in the cellar or the garage while the green fruit ripens. They do not need light to do this.
• Harvest leaf lettuce, mesclun and the like.
• Remove the spent bean and tomato plants, etc. and put in your compost.

Compost and Leaves

• Put spent annual plants in your composter or compost pile in layers with fallen leaves (shredded with your lawn mower). Alternate 1 part green stuff with 3 parts leaves.

• Steal leaves from your neighbours who have put their leaves out for recycling pick up, neatly pressed into paper bags for you to take home and compost. Free fertilizer.


I think I mentioned this last week but it is definitely worth repeating.

• Fertilize your lawn – this is the most important application of the year. The nutrition that your lawn receives this time of year will not produce a great looking lawn this fall, but it will strengthen the grass roots and prepare the plants for a fast green up come spring. The results are less snow mould and a stronger, green lawn after the spring melt. Look for a slow release nitrogen product, like Golfgreen fall formula, for best results.

Plant Colour!

Remember that there are plants that will survive and even thrive in cold weather. Belgium Mums, New England Asters, Sedum Spectabile and ornamental grasses all look great this time of year. Don’t forget flowering cabbage and kale: they improve their looks with frost!

Pumpkins, ornamental grasses, corn stalks, hay bales and goose necked squash can all play a part in an entrance display at the front of your home. Be creative and have fun.

A Short List of things to do in the Garden

October 12, 2011

• Fertilize your lawn – this is the most important application of the year. Use a slow release nitrogen product for best results. I use CIL Golfgreen Fall Lawn Fertilizer.

• Cut your lawn (maybe for the last time!) about 2 ½ inches or 6 cm high.

• Dig your carrots, leeks, left over potatoes etc. and store in bushel baskets ½ full of pure, dry sand. Put in your basement or fruit cellar.

• Yank out your annuals and finished veggie plants. Put them in your composter or compost pile.

• Plant Holland tulips, daffodils, crocus and the like.

• Begin thinking about winterizing your roses that are not of the ‘shrub’ type. Hybrid Teas, Grandifloras, Floribundas etc. will need about 50 cm (1 ½ feet) of fresh triple mix piled up from the bottom. If you live on the Prairies, now is a good time to do this. In central Canada and the Maritimes the best time is just before the Grey Cup game – the game is your reward for doing the job!

• Clean and sharpen your lawn mower before you put it away.

• Wrap spiral plastic collars on young fruit trees to protect them from rodent damage.

• Spray broad-leafed evergreens with Wiltpruf (an anti-desiccant) to prevent the drying effects of winter wind.

• Wiping down all of your digging and cutting tools with an oily cloth.

• Rake fallen leaves off of your lawn and on to your flower beds where the earth worms will pull them down into the soil. Good insulation for your perennials this winter.

• Empty your compost bin of last years’ material and fill it with new.

Enjoy these last few days in the garden before the hard frost of late fall. The air is clear and hopefully you will receive some sunshine for your fall work days!!

Digging and Storing Dahlia Tubers

~October 5, 2011

This is the time of year to harvest dahlia tubers, before or after the first hard frost. If your plan is to dig the tubers early you need to cut the stalks down to 8-10” above the ground. This prompts the formation of nodes on the tubers. If you allow your dahlias to experience a hard frost the stalks will dieback naturally.

Use a garden fork to loosen the soil around the tuber. Carefully lift the tuber out of the soil and wash gently to remove remaining dirt. Allow the tuber to dry for 24 hours in a cool, dry location.

This is a good time to divide large dahlia tubers into smaller sections. Each new division must have an eye (bud) to produce a new plant. Use a sharp, clean knife to divide tubers into sections.

Place tubers in a cardboard box with sawdust, dry peat moss or vermiculite. Label the storage container to help you identify the tubers next year. Be sure to dust the tubers with Green Earth garden sulphur powder to prevent rot and disease while in storage (it is harmless to pets and children).

Choose a storage location in a dry area where the temperature will remain near 10 degrees C or 48 F. Check on the tubers periodically during the winter. Look for signs of shriveling. If the tubers are beginning to shrivel I recommend that you moisten the storage medium to ‘beef’ them up again. But be sure to check weekly for mildew or rot.