A brief history of my involvement in exotic gardening
My interest in growing something more interesting and more exotic started in May 1995, when I spotted some nice (but small) cordylines at my local garden centre. I had already seen many huge cordylines growing in local gardens, so I didn't have any doubts about its hardiness in the local climate.... so I took it home and plated it in a prominent position!
Me & my first cordy - August 1995 (in case you're wondering, I was on my way to a wedding...)
The cordy grew well through an exceptionally hot summer and warm autumn, but for 5 days at the end of December we had a period of exceptionally cold weather, with the minimum temperature on at least one night reaching -7°C (19°F). Worse still, the maxima were barely above freezing. I didn't know about protecting plants back then, and even if I had known, I wouldn't have believed that my small cordyline needed any (it wouldn't have during a normal winter). The cordy looked ok after the cold snap, however it had suffered some damage - a couple of weeks later the trunk collapsed and it was at this point that I noticed that the centre spear pulled out. The plant appeared to be toast. In addition, a few other young cordys in the area had suffered a similar fate.
Cold snap - December 1995
This was the low point for me. I thought that the cordy was the only "palm" that I could grow, and now I couldn't even grow it reliably :-(.
Approximately 3 months passed, and in the spring of 1996 I got myself connected to the internet for the first time (how did I ever live without it!). In the course of my surfing, I stumbled upon Leonard Holmes' site "Growing hardy palms" and was amazed to find that he was talking about 20 or so palm species with hardiness in the 0 - 20°F range!! Further investigation on UK-based sites revealed that some palms (not to mention bananas, yuccas, tree ferns....) were indeed hardy to very low temperatures, and that a thing called 'trachycarpus fortunei' was probably the best palm for British gardens. Well I had heard of this plant before, probably in Fiona's RHS encyclopedia, which listed it as being barely hardy to -5°C (I take their figures with a large pinch of salt now!). It was also at this time that I found out that my cordy wasn't even a true palm!
Could it be true? Could I really grow true palms in my garden? There was only one way to find out, and that was to try it! In the late spring or early summer, I ordered some plants from the Palm Centre. Looking back, they were a fairly 'safe' mix - trachycarpus, chamaerops, butia, rhapidophyllum, sabal minor and musa basjoo (small plants). I had also managed to buy a small trachy from my local garden centre. Anyway, these plants settled in well, although they didn't grow too fast!
Another little encouragement came in in late summer when I spotted leaves growing where my cordy had been, while mowing the lawn. Actually I mowed the cordy! Not only did my first cordy grow back, but in early 2004 it was 10ft (3m) tall! It seems that while these plants can be cut down by temperatures of about -7°C for small plants and possibly -10 for large plants, they are almost impossible to totally kill. Further note: It was cut back again by an incredible -11.6C in winter 2010/11, but is growing back.
Back to 1996 - summer turned to autumn and while I knew that colder weather was inevitable, the first frost came unexpectedly one Saturday in mid-November when I was out for the day. I recognised the signs - clearing skies, light winds, and it was already beginning to feel cold at 4pm! Eventually arriving home at approximately 8pm, I noticed that frost was already beginning to form (unusual for mid-Nov). I hastily wrapped some old blankets round my plants and hoped for the best! The next morning everything was quite white with frost (don't think the overnight low was too bad though). It's funny now looking back how worried I was about even my trachys, but at that time I hadn't proved them for myself and wasn't too sure how they would react to cold weather. I protected all of my plants for the duration of cold snaps for the first couple of winters...
The next 4 winters were normal or mild, so winter protection ended up being unnecessary for all but the musa. The plants grew slowly but surely, only the sabal having given up the ghost, and this I believe more due to lack of summer heat rather than winter cold. I added a few more plants - another musa basjoo, dicksonia antarctica, chamaedorea radicalis, trachycarpus martianus & wagnerianus, 2 more cordys, and even a phoenix canariensis and an agave. Then came my plants' biggest test to date....
The 27th December 2000 started off as a cold but dry winter's day. However around 3pm some snow started to fall. Unusually, however, it snowed heavily for four hours, leaving 6 to 8 inches of the horrible stuff on the ground. Concerned initially about the weight of the snow, I cleared it off my plants and wrapped the musas in blankets. By this time the sky had cleared and the temperature began to plummet, reaching a minimum of -5°C (23°F). The next day was one of the coldest I can remember. In fact I believe that the maximum temperature was a little below freezing, something which 'never' happens here! Having been out for much of the day, I returned at around 3.30pm to find that the temperature was already down to -4°C (25°F). Worse still, the BBC were forecasting an unthinkable low of -15°C (5°F) for parts of N.Ireland that night. Horrified, I threw what blankets I had round all of my plants. It was now 4pm, the sun was just setting and it was -6°C (21°F). It actually felt awful, I don't think I have ever felt it so cold here. I went inside, extremely concerned for the garden I had spent so much time planting & looking after.
That night some inland valleys (frost pockets) did experience temperatures as low as -13°C (9°F) - this was truly exceptional. Thankfully the minimum where I live near the coast was -8°C (17°F), and only for a very short period - however this was still horrendous as far as I was concerned. The cold snap lasted for another 2 days, but mercifully the daytime highs were a couple of degrees above freezing and the night time lows were less severe: -3 to -5°C. Anyway the outcome of all this was that only 2 of my plants were lost due to the cold - an agave that I had tried in the garden during the previous summer and my dicksonia tree fern (I was surprised at losing this one). I had previously lost my phoenix and t.martianus, but not due to cold (these plants hadn't looked too good from the start).
The Dec 2000 cold snap was at least as severe as that of Dec 1995 (actually I believe more so) and I was very pleased that most of my garden had survived! Recent winters were more normal/mild, up until 2009/10.....
2009/10 did not start particularly cold but there was a bit of snow on 20th December. Christmas Eve and Christmas Day started very cold (-4C/25F) but things turned a bit milder from Boxing Day onwards. However despite rain on a couple of days the temperatures remained low, with highs around 4C (39F). The cold returned for new year with -3C (27F) to start 2010. It was then a little less cold for a few days before more snow on 6th January. There was then an extremely rare event on 7th when fog kept the temperature slightly below freezing throughout daylight hours. After dark the temperature dropped further, to a overnight low of -6C (21F). On 8th, unbroken sunshine managed to help the temperature creep a few degrees above freezing, but clear skies meant that once again it plummeted after dark. Initially only to around -4C (25F) - although even this is our average annual minimum! However later that evening an extraordinary thing happened - a stiff breeze picked up. I say strange because normally a breeze is a good thing as it can prevent the temperature plummeting further. Not in this case though - it appears that the breeze, which was blowing off the land, was actually blowing colder air out towards the east coast, resulting in an overnight low (recorded around 11pm) of -8C (17F). The nights of 7th and 8th January were the only severe (significantly below the average annual minimum) lows of the winter.
Now by this time I had gone the extra mile with protection on some of my plants, since anything planted since 2000 would never have seen temperatures anywhere near as severe as this. However around midnight the breeze dropped and the temperature started to creep slowly upwards again. On waking the next morning I was pleasantly surprised to see that the temperature was about -0.5C (31F) and still crawling upwards, although cloud had moved in and there had been a further dusting of snow. A high of only 1C (34F) that day was unimpressive to say the least, although very obvious was the sound of dripping as a surprisingly significant thaw of lying snow took place. That night the temperature dropped again under clear skies, but stuck at -1C (30F). The next day saw somewhat of a change, with rain/sleet. For several days more though, the weather remained fairly cold, with cloud cover and small positive (celsius) numbers both by day and by night. There were then 2 weeks of properly mild weather, making 3 weeks in total without temperatures falling below freezing - not in the least bit unusual in a normal winter, but in 2010.......
Right at the end of January there was a little more snow, but it only lasted a couple of days into early February, and temperatures only fell slightly below freezing. There was then another week and a half of quite mild weather. By mid February, however, cold weather was returning with frost and eventually a bit more snow. Temperatures were not exceptionally low, but once again it was the duration of the cold that was surprising - the cold theme continued for the remainder of the month with normal temperatures nowhere in sight on all but a few days.
Lowest temperature in February was -3C (27F), although (astonishingly) throughout the first two months of 2010 the temperature never even reached 10C (50F)!! Highest in January was +9.4C, highest in February was +9.6C. The seemingly impenetrable +10C barrier was blown away almost as soon as March began, but even then the cold refused to go away, with an unusually persistent high pressure system giving sunny days and cold, frosty nights (down to -2C/28F). From 11th March onwards though, things changed for the better with mild, quite dry, and often sunny conditions. Spring was here at last! Oh wait...... the story doesn't end just yet unfortunately :(.
On 30th March Northern Ireland was hit by a freak winter storm (yes I did say winter). Two days of persistent rain and very poor temperatures culminated in sleet & wet snow falling overnight on 30th, with gales (an extremely uncommon weather feature this winter), leaving some without power. The 31st was showery but the showers were wintry in nature, with April fool's day turning out sunny and chilly. After a few more cold days, mild weather resumed for Easter Monday (5th April). In all of this the lowest temperature recorded was 0C (32F) on the morning of the 1st.
And even that is not the end of the story. The hateful northwesterly flow returned in the 3rd week in April. By this time we were just past the average date of our last frost, but there were still a couple of days of ground frost and an air frost on 22nd. Since the last frost is defined as the last air frost (0C), the 22nd was the last spring frost of 2010, although.......
For a few days in May the northwesterly flow returned yet again and brought a very slight ground frost on 10th & 11th May. I couldn't remember when my last ground frost in May was, but I'm sure it was at least 15 years previous. For this to be achieved the northwesterly pattern had to have isobars stretching right up into the high arctic. Very unusual indeed!!!
What I should say about April is that mainly settled weather brought quite chilly nights throughout the month, but with often warm and sunny days, one or two up to 19C (66F). This was also a feature in May, with one weekend seeing temperatures up to 26C (79F). May also brought milder nights, which helped the trees, many of which were struggling to put on spring growth.
In early March we discovered that winter 2009/10 was officially the coldest in Northern Ireland since 1962/63 (a legendary winter which itself was the coldest for over 200 years). Normally our cold spells are infrequent and short, I don't ever recall seeing persistent cold like in winter 2009/10. It's changed my view of the climate here and future plantings will definitely bear it in mind! Anyway I hope/trust/pray that it is a long, long, long time before we see anything like it again!!
So, this is a page about my interest in exotic gardening, so how did my garden hold up? Well there were some losses - a couple of agave americanas, one opuntia. It takes some time for damage to show, and even longer for the final result to be known. Quite a few plants showed more minor damage, e.g. leaf browning/spotting, but many grew back strongly.
Another addendum to this story was winter 2010/11. While not as severe overall as 09/10 (due to a near normal January and a mild February), December 2010 was a shocker with two exceptionally prolonged cold spells - one lasting from the last weekend in November until around the 10th December, followed by a mild week, then a second, much more severe, spell lasting from 17th to 25th December. Both were accompanied by snowfall. Some quick statistics from these parts:
- Coldest December for more than 100 years
- Multiple all-time record lows; previous Northern Ireland record low of -17.5C (0.5F) broken by over a (celsius) degree: -18.7C (-1.7F). At my house, -11.6C (11.0F) recorded.
- December temp 5.4C (9.7F) below normal.
- 3 or 4 freeze days in one week at my house (to put that into perspective, I've only recorded 2 freeze days in the previous 18 years)
- Nearly 20 days of lying snow in December at my house, compare that with the normal 4 or 5 days for an entire (average) winter.
- 8 inches (20cm) of snow in the second spell...... ironically the depth may have protected some plants as the ground didn't freeze where the snow cover persisted.
It's funny how things average out though, as after Christmas the rest of the winter was snow-free at my house.......
Now once again I could whinge about how bad all this was (and it *was* horrific). But spring 2011 has been very different to 2010 in that the last frost was sometime in March (in 2010 the frost kept coming back and we even had a ground frost in early May). Not only that, but we had a record breaking warm April 2011 in some parts and the warmest Easter for 50 years or so. Really hope 'normal service has been restored' :)
Oh, and as far as plant damage is concerned, things aren't too bad (largely due to my excessive protection given what happened in of 09/10), although the cordylines have been cut back again :(.
Time for a bit of an update (August 2015). After the terrible year of 2010 (early and late), we have now had 4 normal to mild winters. There have been few losses since then, the most surprising was my yucca rostrata, which turned yellow and rotted from the centre. The guys at the EPS forum figured it was delayed damage from 2010, but if that is the case it took nearly four years to appear!! I know latent damage can take some time to appear, but I always understood that to be months! Anyway I've made very few additions since 2010 since I do not want to add to my already high workload should any nasty extreme weather occur in the future. I've added a yucca linearifolia and one or two other new plants, but generally if anything dies now it is frequently replaced with something rock solid like a waggie!