The Devon Inside

"Keep it in the greenhouse for a little while longer, the growth will start quicker. It may be Luton outside but it will be like Devon inside."

Is an advice a nurseryman once told me when it comes to starting off plants in pots in the spring. They start their growth in the new season earlier and the rate much quicker. It makes perfect sense as it gets much warmer, faster in the greenhouse compared to outside hence plants are stimulated into early spring growth. And the warm temperatures are held on for much longer even if the temperatures outside dips down during the evenings and early mornings, a risk that is often associated with early to mid spring.

Devon is part of the west country area of England, a generally milder area as they benefit early on (and much more) from the warm gulf stream air. Because of this the growing season there is earlier and slightly longer than the rest of the country.

It's a really good advice but I made an exception to it when I planted out a special Beech (Fagus sylvatica) cultivar a few weeks ago. It’s a beech after all, definitely hardy and I’m not in a rush to see it in leaf and it can take its natural course, Luton time. (A Beech in an exotic garden I hear you ask? We’re not just into exotic plants but also ones with interesting foliage, and this cultivar certainly has some, but more on this special cultivar at a later post.)

Greenhouse late February

But apart from that beech, pretty much everything else in this particular greenhouse stayed an extra couple of weeks or more inside, just to give them a good head start before they get eventually planted out or placed in their homes outside for the summer. Most of the plants in here were intended to be planted out, but either they are too small still or their intended homes aren't ready yet so we overwintered them under glass.

It may seem unnecessary to put most of them under glass, with frost free heating to boot if they were meant to be planted out anyway, so why not just leave them outside? Some are simply too small still to expose them to the harsh elements of winter, so giving them protection and keeping them ticking during the winter is vital and when they reach a certain size then they can be planted out. Another reason is that they may be fine when planted out but whilst in pots they are more vulnerable and some of them cannot tolerate prolonged rootball freezes which potted plants are more prone to.

The main reason for me though is for aesthetic purposes. Leaving most of them out in the winter, apart from risking their very existence, can take its toll on their appearance and come spring you're left with very tired looking and scruffy plants that will take weeks to recover. There's space available in the greenhouse so why not use it to its full capacity. Come spring you have a group of pristine looking plants ready to be planted out, and makes an instant impact as they look so good for the time of the year.

One thing about gardening and cultivation of plants for ornamental purposes, they are there to look pretty and it gives you a sense of satisfaction when you plant out something that already looks good, instant impact as I've just mentioned. And boy did I make the right decision. Had if I left most of them out they would have been through the harshest winter we've had here for the past hundred years or so. Either half of them would have died or at least I would have been left with a bunch of tired looking plants that would have taken an entire summer to recover, let alone look pretty.

It's a case to case basis of course, there's the nurturing side to every gardener to consider and not all plants benefit from receiving protection in the winter months. Topics worth exploring in the future :-)

The Greenhouse late March, spot the difference...

Anyway, slowly and gradually I've been taking out plants to acclimatise them to the cooler life outside of the greenhouse. First out were some of the arids and palms, then a few of the shrubs as they were planted out. The only other arid left inside is a trunked Yucca linearifolia. Although well rooted, the pot is small and the top too heavy that if left outside any gust of wind will just knock it to its side, so best left there until it's ready to be planted. With the reduction in numbers, the remaining plants are no longer as cramped as they were before, enjoying the extra space. One plant enjoying the extra space, especially it's starting grow to a relatively huge size is the Zantedeschia 'White Giant', which is currently flowering. I refer to this plant as 'The Belle of the Greenhouse' with its beautiful flower set against a backdrop of foliage, like a pretty maiden surrounded by dapper men.

The Belle of the Greenhouse (Zantedeschia 'White Giant')

Gradually, almost one by one I'll be taking out plants until nothing will be left. Most of them can't stay in there too long either. As the season progress and the temperatures and sunlight intensify, left too long it will have an adverse effect of drying/burning them to a crisp which is just as bad as winter damage. Unless you put some shading but I don't intend to do that as this greenhouse is only temporary. Once all of its winter and spring residents are gone it will be dismantled to make way for some construction work, to be positioned somewhere permanent once that is sorted :-)

Mark