Oak won’t cast a leaf till May is out

Can it be some disorder? Hardly, because the tree performs quite normally through spring/summer/autumn. Then, of course I realise that it is just doing what the beech and hornbeam hedges do every year, and they are also classed as deciduous species. The additional shelter in winter being one of the reasons why they are so popular.

But the mature beech and hornbeam tree specimens don’t act like that by the time they are 4m – do they?

I have always believed that they hold on to their leaves over winter when grown as hedges because they are clipped annually so it is immature growth that acts in this way.

Not being able to remember where the seedling came from, it does occur to me that maybe some clones of oak are known for this variation.

Well that may have something to do with it, but I found part of the answer by asking – no not Google but my colleague George Anderson.

“Och, that is known as marcescence he replied as if it was a word he used every other day. “Aha, but what causes it?” says I.

Here endeth the school day because it turns out that there are various theories about this... could it be a mechanism to protect new buds from severe weather or as the leaves become brittle do they supply a deterrent factor to protect the buds from marauding wildlife.

Or could it be the slightly more ridiculous theory that it is something to do with the nutrient value of the rotting leaves which have fallen in the autumn being lost over winter as the nutrients are leached out? The follow-up reason being – if they don’t fall until spring, they provide an early mulch while simultaneously giving up their nutrients.

At that point I gave up and went to bed.

Well, of course you know what happened then, I couldn’t get to sleep thinking about it.

Finally, I dosed off having satisfied myself that the answer is much more simple. This particular clone comes from a much more northerly latitude and in late autumn it needs a really sharp frost to make the tree shed its leaves.

It’s that climate change thing again, but I did learn a new word – marcescence.

This spring has been marked by strange weather patterns – practically no snow, some rain but ‘not a lot’ in these parts, high temperatures (up to 19°C in our garden) a little frost and with that pattern relentlessly cold winds.

I have referred to this already but mention it again now from the gardeners’ concern for the pollination of early flowering fruit crops. We have plenty bumble bees in the garden, some paralysed with cold at times but as soon as they get a bit of sun on their backs, they are busily at work.

If this pattern were to become an annual occurrence I guess there would have to be some replanting carried out using a range of cultivars which flower later in the season.

There is no problem with that idea so long as we get the predicted longer growing season into the autumn to ripen the fruit.

Fruit grown indoors can be pollinated using a little paint brush though of course if you care to leave the door open the bumbles and others will be appreciative of the shelter and do the job for you – nonetheless you may have seen the aforementioned Mr Anderson tickling a few flowers on our magnificent Cherry tree grown under glass at Beechgrove which I trained into an espalier shape – evenly spaced horizontal branches.

That young oak tree, still clinging on to last year’s foliage

That Sweetheart Beechgrove cherry in full bloom