Gardeners in the BC Lower Mainland area can visit the home of Heritage Perennials® during our annual PUBLIC OPEN HOUSE. Our 27 acre nursery in Abbotsford, BC will be open to the public for tours, Master Gardener consultations, plant sales (including a GREAT bargain area), seminars and more. Food and refreshments will be available. Join us on Friday, September 8th, 2006 from 9am to 2pm at 1831 Peardonville Road in Abbotsford, British Columbia.

The Valleybrook Gardens Ontario GIANT PERENNIAL PLANT SALE will be taking place on Saturday, September 9, 2006 from 9am to 4pm. The sale is at our ONTARIO nursery, located near Niagara-on-the-Lake at 961 Line Four Road.

There will be BARGAINS GALORE!! We suggest you bring your own cart if possible, and a supply of labels could also come in handy. Master Gardeners of Niagara will be on hand to assist and to answer gardening questions.

These two events are the only days each year that our wholesale nurseries are open to the public, so it's a fun opportunity to see where those familiar blue pots of HERITAGE PERENNIALS® get their start!

As much as I look forward to the tours and many perennial gardening topics on the agenda, it's the fellowship with other perennial plant geeks and nerds that's the best part. We all marinate in perennials for a few days, then go home to our own little worlds and feel better about everything. I guess every industry has a thing like this, but when you turn your passion into your career a conference becomes a really big thing personally.

So, I hope to come back with some new plant ideas, tips or tricks at the very least, and to share them with our growing fold of dedicated newsletter readers. We hit over 11 thousand readers a couple of weeks back. Thanks so much to all of you for subscribing!

Shown above is our own Jason Rekker giving a perennial seminar here at our nursery.

I was literally flooded with responses this month. Wow! Mulching must be a very hot topic, and here I was anticipating only a handful of entries. Thanks to ALL who sent in their answers.

I'm relieved we did a draw this time around, and congratulations to our three winners: Karen — Niagara-on-the-Lake, Ontario; Carole — Calgary, Alberta; and Pat — Belfast, Maine. Each will receive a copy of our Perennial Gardening Guide.

I've taken some time to analyze the data, and the results for the #1 question on whether to taper the mulch or to pile it evenly around perennials worked out this way:

• 85% — spread mulch evenly over the bed
• 7% — doesn't matter, or depends on the particular plant
• 8% — taper the mulch or rotting may be a problem

A few people specifically mentioned problems with rotting of Bearded Iris if the rhizomes and the base of the leaf fans are covered. Some had experienced problems with smaller types of spring-blooming bulbs not being able to push up through a deep layer of mulch, Crocus in particular.

DEPTH of mulching reported varied considerably and this surprised me. A large number of you spread mulch to a depth of 2 to 4 inches. A smaller number mulch lightly (1 to 2 inches) and about the same proportion reported piling it to depths of 6 or even 8 inches. Wow!

TIMING varied widely also, but early to mid spring was a popular choice, at or just before the time when many perennials emerge. I was intrigued how many of you mulch in the autumn, partly for additional winter protection but also because it works in your garden routine or happens to be when your own compost is ready to be used and in generous supply. Many gardeners make use of leaves that fall naturally on the beds, or leaves they collect from neighbours. Some said they shred or chop the leaves, others use them "as is".

MULCH PRODUCTS covered the whole spectrum, which points out the value of locally-available byproducts or what your garden centres happen to sell. Some people purchase mulch in bags, some get it delivered in bulk. Several of you put down layers of newspaper underneath the mulch to smother perennial weeds. These are the various products mentioned, in order of popularity:

Bark mulch — the hands-down winner — (cedar, cypress, pine or a combination); leaves; wood chips (composted or fresh); compost (your own or bagged or mushroom); pine or spruce needles; cocoa bean shells; pine or cedar bark nuggets; straw; composted manure; hay (usually spoiled or aged); grass clippings; seaweed.

A couple of people wrote in mentioning inert products, such as stone or pea gravel. One fellow even uses ground-up recycled tires with good results!

BENEFITS of mulching you mentioned included: reduced watering, because the mulch holds the moisture in the soil; cooler roots during summer heat; greatly reduced weed seed germination (figures in the 80% fewer weeds were mentioned a few times); mulches add beneficial organic matter; mulches encourage plenty of soil microbes, worms and other beneficial critters; mulch looks aesthetically pleasing. The most important thing you reported over and over again is that mulching seems to make your perennials grow better!

NEGATIVE CONSEQUENCES of mulching reported were mainly an increase in pests, specifically slugs, snails, earwigs and sowbugs or pillbugs.

CAUTION AROUND TREES & SHRUBS was mentioned several times, and for a few reasons. Firstly, woody stems may in fact be more prone to rotting or developing fungal problems when moisture sits constantly around them because of contact with deep mulch. Also, it may create a haven for rodents, especially around fruit trees. Boring insects may also take advantage of the great hiding place that mulch could provide.

Patty — Saint John, New Brunswick
"I used to keep the mulch back from my plants as that was what I had read as well. I use shredded bark mulch about two inches thick. It dawned on me that in the spring after the wind, rain, snow and heaving of frost over the winter, the mulch was covering pretty well all of the garden. No little round spaces of soil remained, but the plants grew through the mulch anyway, so I no longer worry about it. I now tuck it in all around the plants." [See Patty's photo, right]

Carole — Calgary, Alberta
"Living in Chinook-prone Calgary, I usually have mulched up and around my perennials just because I didn't know any better. Just recently I read about tapering the mulch around perennials in a National gardening magazine. I had never noticed ANY problems before, so I will just keep doing it."

Pat — Belfast, Maine
"It isn't the mulching or not which is the real issue. Rather, it is paying attention to each plant's specific requirements and potential for certain problems. Therefore, with most shrubs and perennials which have the right amount of moisture for the plant, the mulch is up around the stems. If the plant is susceptible to, say, soft rot of Iris, I don't bring the mulch up very close. As with almost all general rules, common sense should be the deciding factor."

Janet — Meaford, Ontario
"As a professional gardener and Horticulturist, I am a strong advocate of mulching — for all the good reasons. The type of mulch most readily available in my area is shredded cedar or a pine/cedar combo. I have not experienced any problems with rot; however, I have seen, in some cases, where the mulch has been laid very thick (3-4 inches), a buildup of what appears to be a fungal growth between the layers of mulch. This growth does not seem to cause any problems for the plants and, I believe, there is some truth to the theory that one type of fungus may be antagonistic towards another, thereby reducing the growth of some of the more harmful garden fungal diseases. I always keep the mulch several inches away from the base of woody plants to reduce the possibility of small rodents nesting in those areas over the winter."

Barb — North Bay, Ontario
"I have recently replaced my entire front lawn with various perennials. I started on one side two seasons ago, and did the other half last season. Being a novice gardener when I started, I hadn't heard about leaving space around the plants, so I just mulched the earliest garden right up to the plant crowns. By the next season, when I was completing the other half, someone had told me that my plants would suffer if I didn't leave space around the crowns, so I did just that.
I have to say, the first half of my garden sprouted far fewer weeds and suffered no ill effects that I could see. I now mulch right over everything in the spring, and things seem to come up just fine."

QUESTION: "I have a problem with earwigs on my plants. I have tried using a powder that was recommended for earwigs but it is not proving effective. What can I use to get rid of earwigs and all the bugs in my garden that is safe for my plants?" Susan — Kitchener, Ontario

ANSWER: Bear in mind that along with harmful bugs or pests, there are hosts of beneficial ones that are helping to keep the bad guys under control. If you get rid of these as well, your garden is open for being attacked once again by the bad guys with no beneficial ones to help keep them in check. Toxic chemicals that kill bugs also affect birds, amphibians, pets and humans to at least some degree.

Gardening has moved from a war to a compromise in recent years. None of us want to be out there using toxic products constantly. The idea now is to keep pest levels to a tolerable level, rather than elimination. I figure, if you can't see the damage from ten feet away it's really not all that bad and most of us can live with it. A few chewed leaves is not a cause for panic, really, but sometimes the damage done is much worse.

Having said that, I encourage you to explore the new world of more environmentally friendly products that every garden centre now stocks. Soap-based insecticides are effective on a wide range of common insect pests. There are other types that are bacteria-based that zone in on very specific pests, and these are terrific if timed correctly according to the label directions. You can also find predator insects that feed on the "bad" kinds, as well as parasitic nematodes that work well on things like lawn grubs.

The real key is discovering what your pests really are, then having a strategy to deal with each specific kind. Your local garden centre will be happy to help you figure this out, just take along samples in a plastic bag. There may also be Master Gardener clinics held in your area on a regular basis, and these trained volunteers will also gladly help.

In terms of earwigs, there is NO way to eliminate them entirely, since most of southern Ontario has been infested for many years now. Control can be achieved, but there is no magic pill i.e. nothing that works so well that you can just apply it once and have it work for the entire season.

I'm not big on kitchen remedies, but here is what I do — get aluminium tart shells and sink them in the soil so the rims are level with the soil surface. Put 1 inch of soy sauce in them, and 1/4 inch of vegetable oil. Check these in the morning and remove the dead earwigs. Top the traps up as needed, and don't forget to dump and replace the contents after a rain storm. You will soon find certain "hot spots" in the garden where there are loads of earwigs, and other places they hardly go at all. It's amazing how many earwigs one of these simple traps can catch. They are attracted to something in the soya sauce (probably yeast) then slip inside and drown under the layer of oil.

Start trapping earwigs in late April and early May next year. The adults tend to their own young, so the more you trap early in the season, the fewer will have a chance to breed and make the next generation. It's still worthwhile trapping them now, however.

My idea with this is to start building a library of perennial plant problems and pests. So... Valleybrook Gardens/Heritage Perennials reserves the right to make use of any photos sent in for this contest on our website or in future newsletters, with credit given to the photographer. These must be your own original pictures!

This month we will select the THREE BEST photo entries, and each winner will receive a signed copy of the Perennial Gardening Guide. Winners will be announced in the August newsletter, along with a sampling of perennial pest photos.

Our best-selling book, the Perennial Gardening Guide (4th edition, March 2003) is a handy reference used by gardeners across North America — written by John Valleau, horticulturist for Heritage Perennials®. Available at your local Heritage Perennials® Dealer.