Plunges

[Alex]

Another of my probably silly questions, I'm afraid.

I have never grown with plunges, so know nothing about them. However, I am thinking about getting some plunges and want to ask - is it possible to grow in them without watering into pots directly i.e. can the pots ever get all they need from the plunge (clay pots, obviously)? Or does there always need to be some actual watering into the pots? I'm talking about a collection of various different bulb species, by the way.

Thanks,

Alex

[Carlo]

Alex,

Plunges are and excellent way to grow potted material (primarily clay-pots). I don't know, however, that you will get away from pot watering. During the growing season the plants need more than they're likely to get from the plunge material itself. During the DORMANT season, nearly all watering (which should be sparing anyway) can be accomplished through the plunge itself.

[Gerry Webster]

Alex - I've always grown bulbs in clay pots in plunges, both covered & uncovered. I agree with Carlo that, for the most part, one needs to water both the pot & the plunge. However, there are exceptions. Thus from about November until it begins to get warm, I find that cyclamen are happy if the plunge alone is flooded about every 7-10 days.  My plunge beds are  60cm raised beds filled with 30cm of rubble & 30cm of coarse sand; they drain into the ground.  I think one has to discover by trial & error the appropriate watering regime for the pots & the plunge.

[anne gibson]

Alex, like you I also ask silly questions-except they are not silly at all. I  am at the foot of the very steep learning curve which is the care of alpines! I made the mistake of thinking I just watered the plunge but found that even last year the plants were not getting enough water. Eventually it clicked that a combination is needed. However  in  the dormant period using a plunge does make it a lot easier especially for the plants which need to be kept a bit damp.

[Maggi Young]

Alex, like you I also ask silly questions-except they are not silly at all. .

Quite so, Anne, no such thing as a silly question in the quest of knowledge.........any question you need an answer to to learn something has to be useful

[Diane Clement]

Another of my probably silly questions, I'm afraid.  I have never grown with plunges, so know nothing about them. However, I am thinking about getting some plunges and want to ask - is it possible to grow in them without watering into pots directly i.e. can the pots ever get all they need from the plunge (clay pots, obviously)? Or does there always need to be some actual watering into the pots? I'm talking about a collection of various different bulb species, by the way.  Thanks,  Alex  

There's no such thing as a silly question.  If you need to ask it, it's not silly!
A sand plunge needs to be as deep as possible.  It then offers protection to the roots when the air is too hot, or too cold.  It also acts as a soak away if you over water, and because it holds a reservoir of water, it also helps if you under water.  
However, it does not stop the need for watering the pots.  Clay pots cannot take in water through the sides to the compost, although the sand plunge will stop evaporation from the sides.  The only way that water can get from the sand plunge to the pot, is via the roots through the hole in the bottom of the pot.  Often, the roots move through the base hole into the sand plunge.  I always see this as a good sign as it means the pot is not too wet and the roots will only take what they need from the plunge.  The problem can be then trying to remove the pot if the roots have moved a long way - it involves a careful excavation!  This action mimics nature, where the roots travel down through soil and rocks in search of water.  

When and how you water depends on what you grow, and you may need different plunges for different types of plants.  However, for most of the year, for most plants, I water directly into pots.  Cyril Lafong's excellent article in the recent SRGC bulletin explained that he uses a lance on the end of a hose, which is a very useful way of doing it as you can target precise areas very easily.  In the winter, if cold, I will water just into the plunge.  For alpines in the summer, I soak all the pots and saturate the plunge until it is dripping out, which can last over a week without extra watering (useful for holiday times).  For bulbs in the summer, I water only into the plunge occasionally, although some bulbs get removed from the plunge and get none at all (junos, oncos).  

You need to experiment yourself a bit with the plants, pots and compost you use.  It is impossible for someone to mimic someone else's conditions, which include our individual climates and how much watering time you can allocate each week (I have a lack of the latter, so use plastic pots for quite a lot of things).  So what you must do, is keep an eye on things to see what's going on.  Constantly check the water in the pots.  If the gravel looks dry, that is no clue as to what's going on below -  I often shake the gravel off carefully to see what the compost looks like.  I also use a little moisture meter which is a cheap instrument with a little dial and a metal probe - not particularly accurate and quite variable as to the type of compost used - but very easy and quick for checking a lot of pots.
Good luck, we look forward to seeing the results.  

[Diane Clement]

A sand plunge ... offers protection to the roots when the air is too hot, or too cold.  It also acts as a soak away if you over water, and because it holds a reservoir of water, it also helps if you under water.  

I am reminded of a quotation (by Gladstone??) concerning the contradictory effects of tea.  I've probably misremembered it, but it goes something like this:

If you are cold, tea will warm you up.  If you are hot, tea will cool you down.  If you are tired, tea will wake you up.  If you are excited, tea will calm you down.

Some people might apply more accomplishments to gin, or even to chocolate   

[ranunculus]

I am reminded of a quotation (by Gladstone??) concerning the contradictory effects of tea.  I've probably misremembered it, but it goes something like this:

If you are cold, tea will warm you up.  If you are hot, tea will cool you down.  If you are tired, tea will wake you up.  If you are excited, tea will calm you down.

I suggest it was Casanova, talking about s*x!!!!!

[ranunculus]

I didn't even know that Casanova grew sax!!!!!

[Luc Gilgemyn]

He clearly was a man of many talents Cliff...   

[Diane Clement]

I didn't even know that Casanova grew sax!!!!! 

Well, I'm sure he didn't have time to drink tea 

[Joakim B]

Casanova was a hot chocolate man if anyone will go by what he writes in the book(s).
Not admitting to have read the books just to know that he was drinking hot chocolate according to the book(s).
Joakim

[ranunculus]

If people now Google 'Casanova' will they be directed to the S.R.G.C. .... !!!   

[Diane Clement]

If people now Google 'Casanova' will they be directed to the S.R.G.C. .... !!!    

It's only those that search "Casanova" AND "ranunculus" that will get there 

[Tony Willis]

Alex

I moved from plastic pots to clay plunged in sand about sixteen years ago when living in Nottingham. I used to come home in the evening from work and find the plastic pots were almost too hot to hold haveing been baked all day in the sun(yes the greenhouse was shaded) and the plants were dieing.

In Chorley I have had all my plunges in the greenhouses and frames on the floor mainly on flags apart from two. This has presented a problem not only with getting down to the plants but with my high rainfall, seepage means they never dry out. For plants like many hardy cyclamen this has proved okay but many others which need more drying in summer have not been happy. I am at present moving the plunges in my greenhouses of the floor. The two off the floor have heating cables and are used for more tender plants such as gesneriads and ophrys and the other cyclamen graecum which I keep frost free

The advantage of this particularly with say crocuses is that I will be able to sort them into groups with different moisture requirments.

As to watering at this time of year with the bulbs I water the pots but not the sand and this seems to draw out excess water. Other plants like ophrys I have only watered the sand and they have drawn in sufficient water for their needs. As spring advaces I water  both the pots and sand plunge for all the plants.

With arums I have these in pond baskets and they grow out of these into the plunge. Here I feed both the baskets and the plunge.

You mentioned having got a Crocus pelistericus from Jim Archibald a bulb I have had some success with. I would say this will not grow inside even if plunged. I grow mine outside  in a shady sand plunge which is uncovered all year round and is open to all the elements.They are constantly wet and cold.