And what is a Minnesotan  supposed to do when it is  April 09, 2012, and  it is already May 15th in the landscape garden, and frost is in  the forecast for the evening?   

French  lilacs in open sun are about to bloom, redbuds in the city are already opening their flowers, crab apples appear about to open theirs as well and the temperature is expected to drop to 26F tonight.

If your  tomatoes were already set out and growing, they would have to be covered or become  dead by morning.

Fortunately,  most of the woody plants we enjoy in our landscape gardens or settings are too hardy to be bothered by a light  frost in a very early Spring.   But what about an normal frost in “late” Spring.    What might be expected.   Well, more frost in the future, for one item.

One of my most beautiful trees in bloom is Elizabeth Magnolia.   The tree structure isn’t much to admire, but the blooms are much more than impressive…..and if you like large,  soft yellow  almost waxy petals of Southern style to show off here in the Twin Cities, Elizabeth is your tree. 

My Elizabeth is about ten years old in its space, a hide away no one ever sees in my landscape garden except for its owner.  It usually opens its show around Memorial Day, yet its buds are now already about to explode  in another warm day or two.    What damage will the frost cause?

I live in a mid tier western suburb of Minneapolis, outside of the isotherm surrounding the more ‘cemented and paved’  Twin City metropolitan area.    My Elizabeth wouldn’t have a problem if the evening’s cold dropped to only  30F.   We don’t call this cold a hard frost, but 25F IS  a cold frost.

What about my intersectional peonies?   They are rather expensive perennials and not as reliably hardy as  traditional peonies.   Tree peonies shouldn’t  be troubled by the spring cold, but what about intersectionals?     Well, do as I just did this very minute ago…..thinking about my beautiful yellow intersectional, I just now came back from covering it with a size twenty horticultural pot……big enought to cover safely a foot and a half cluster of the peony’s new growth.

There are about 100 newly potted perennials I have dug   from this spring’s garden produce already.   They are sitting in an small tree covered area to the south of my house.   They are on their own…..and unless the temperature drops to twenty degrees, I am not particularly worried about their welfare.

In general, with the exception of  intersectional peonies, I dont worry about any of my two hundred or so herbaceous perennial species  in my landscape garden  being damaged or killed  by a spring frost, this year or any year.    If a leaf or two is damaged by frost  on early growth, there will be renewed growth.

Althoug my Elizabeth tree won’t be damaged, but her  buds might be.   They may freeze and refuse to open and turn ugly brown for this spring’s display, or the edges of the blooms may become discolored.   That would be painful for me.

We shall see.

No conifers will be bothered by this year’s early spring warmth and frost combo, either in foliage or growth.  

If the cooler temperature persists for a couple of weeks,  our garden plants will hold back on their growth and return more or less to the regular seasonal growth patterns.

You may have noticed that most of your hostas not growing on sunny exposures on the south side of your house haven’t shown much interest in poking their noses above ground despite this wonderful warm 2012 spring weather.    Those which have leafed out might  show some leaf wrinkle or discoloration due to a hard frost, but no matter the plant will simply supply you with countless other leaves as if nothing untoward  ever happened during the evening of April 9, 2012.

If your apple trees had just opened bloom and the cold weather lasts for several days, don’t expect to have much of an apple crop this autumn.

For longer lasting spring blooms, whether tree or herbaceous perennial, a cool, windless, rather dry spring will yield the best floral display over the longest period of time  possible.   My redbuds, the six to ten that I have somewhere on the grounds have been in swollen bud for nearly three weeks, showering each tree crown with a mist of hot pink awaiting to explode into full form.   I don’t expect the frost to cause trouble here, since there is no sleet forecast to accompany  the cold.

Do keep record of when your plants come into bloom.   Be aware that the East side of the house is almost always the best aspect for garden planting displays all other conditions being equal.      It will improve your artistry  in placing plants for better displays in the future.     Toka plum, PJM Rhododendron  are in full bloom when redbuds are in lacy appearing full bud nearly every year…..and what a beautiful display that is to witness when you have cleverly positioned them.   Imagine too, spreading green and aqua junipers and pure white arabis rockcress added for further color emphasis……and an accent of Weekend Forsythia in the distance.

Call us for consultations,  tours, or help  landscaping your home or business grounds to enjoy or  learn more about the art of landscape gardening…   Masterpiece Landscape, Ltd….952-933-5777.