Sand beds

[Tim Ingram]

Extending the sand bed
Gardening with trees and shrubs, or even perennials, requires more space to move into as your fascination with the subject expands. With alpines at least small incursions into the lawn pay big dividends! (If your other half is not there to remind you that there are many other more important things that need doing!). The relatively small sand bed in our front garden is now pretty full and new acquisitions this autumn really require room to show themselves off. To extend the bed is quite easy, as the photographs show, but even this very small area has required the removal of around half a ton of soil and infilling with fine sharp grit. A hard morning's work!

[Tim Ingram]

The 'sand' used is very fine potting grit derived from shattered flint and the picture below shows this in close up. It would be interesting to compare results with sharp sand or ballast as more normally used. As I have mentioned before it is probable that these would hold more moisture and require less watering than I have had to do in dry periods. I have two large pieces of tufa left over from a previous raised bed and therefore have added these to provide some relief. It would have been very nice to use a lot more tufa associated with the bed, and David Sellars, a North American grower with experience of sand beds and tufa recommends that the two associate very well. I imagine there would be very good transfer of moisture from deep sand to blocks of tufa. Even the two blocks here make an appealing feature.

Positioning plants and planting them is very enjoyable and easy in sand. I don't wash the roots of soil as some growers recommend, but do pay close attention to watering the newly planted area over initial weeks. It can then take a year or even more for some plants to really establish and grow away, but as a consequence they stay tight and in character and much less prone to pests and diseases.

[Luc Gilgemyn]

Well done Tim !!  I always find it exciting to have more planting space available ??  Especially with such a variety of gems waiting to find a suitable spot !!  

[Maggi Young]

The 'sand' used is very fine potting grit derived from shattered flint and the picture below shows this in close up.

My, yes, that is very sharp looking stuff. You'd hope cats and slugs would find it very uncomfortable, wouldn't  you? 

[tonyg]

Looks like something I should try .... we have pure sand only a couple of feet down already.  Maybe I would need to pay attention to watering for longer than a year!  In spring 2011 plants which had been planted out almost a year earlier began to curl up as drought took hold.

Where do you buy that lovely looking sand?  Here the sand at garden centres is relentlessly  (sandy) orange in colour.

[Martinr]

Tim, I presume the sand will weather to the same colouration as the rest of the bed?

[Tim Ingram]

Thanks Luc - things can happen quickly on this forum! I have been inspired by your tufa blog but have yet to get my tufa!! So for the time being I am devoting my attentions to the sand bed. Maggi - It is certainly true that slugs seem deterred as all of the campanulas on the bed are untouched! Fortunately we have no cats around; I think they might find it more amenable! I think the great variation of particle size is a good benefit and must help in holding moisture by capillarity. Tony - the 'sand' is left over potting grit that we had in bulk for the nursery. It is heat shattered flint (Canterbury Spar) and, I think, is the fine stuff left over when they have graded out the material used for rendering house walls and the like. I am not sure if it is readily available outside our area? Martin - as fast as I aim to reply I am beaten to it!! No what I have done is to surface the bed with 6mm gravel, partly because the fine grit is rather bright and partly to improve the aeration around the crown of plants. Each year I topdress with another layer of gravel so this gradually becomes deeper. I think it is a particular benefit for certain plants like the daphnes over winter.

This new area provided space for about 25 plants and there will be the opportunity to establish more in the tufa blocks (which have ready made holes in situ!). They should have a month or more of good growing weather to begin to establish and around the end of October the bed will be covered with Dutch lights through to early spring. Little if any watering will be necessary over this period unless we have long unseasonably dry and warmish weather (usually in late winter turning into spring).

What of the plants? They vary considerably and with a number I am being quite adventurous! They include several choice campanulas that generally succeed well in sand, silver saxifrages, succulents like Delosperma cooperi and Rhodiola trollii, dianthus, onosma (often short lived but very appealing), Pulsatilla vernalis (again! - I would really like to establish this), and a good number of others from various genera. With other sections of the bed drawings have been made to keep a record of the planting (particularly important when one wishes to propagate from the plants, as is a primary aim of the planting). In the digital camera age I have just begun recording newly planted sections of the garden photographically and appending plant names on a wide border around printed copies. However much one thinks names will remain in the mind they quite quickly become lost unless plants are being managed all the time. After what seems quite good success with many plants on the initial planting of the bed, I look forward to seeing how this new planting develops next spring (and keep my fingers crossed that no rabbits discover it!).

[John85]

Tim it seems that your sand bed is roughly at the same level as the lawn.Does it not drain the humidity from the surrounding area and fill with water at the bottom in the winter,or is your soil very free draining?
Till now I have constructed all my sand beds one foot above the ground but it is a core to water them in the summer and most of the time one is not even allowed to do so.Therefore I was thinking of lowering them down but my soil is heavy clay and I am afraid I may lose plants in the winter, even with a cover,because the roots may be too wet.What do you think?

[Hoy]

I wish I had space to make a sandbed!

Unfortunately I have to clear my woodland to get space but that is out of question or the time being - there are some choice woodland plants too
However I had the same thoughts as John85: Your subsoil has to be very free draining. If I had made a bed like that (same level as the lawn) I had gotten a lake in fall even with a rather free draining subsoil.

[Tim Ingram]

John - I deliberately made the sand bed below soil level because we do have naturally well drained soil and a dry climate and I hoped that this would keep the sand moister during hot and dry summer weather (not really too different to the traditional scree which is normally made at ground level). Even so I have had to water quite often this year, although this is largely because many of the plants are still small and haven't established a deep root system. In winter I have found cover is essential to prevent the bed becoming too wet, though that is mainly because I am trying some pretty choice plants in it. (Growing in tufa or a crevice garden would probably enable many more plants to be grown without cover). On heavier clay soil I would definitely construct a bed above ground level. Since watering sand is very easy and the plants so special I think it is as valuable to keep an eye on this in the garden as it is in the alpine house or troughs (I have the fern Asplenium ceterach on the bed and this is a good indicator plant of drying out, though I don't usually leave watering this long!). Again I would cover the bed in the winter and have even toyed with the idea of an all year round covered bed for plants from really dry climates (viz: Roy Elliott's famous tufa wall), but this would require some sort of dedicated watering system so becomes a more complex exercise!

Trond - I think sand beds can come in any size! From Peter Korn's quite epic scale down even to troughs or a small raised bed (but I have to admit I have neglected some other parts of the garden while I have had fun doing this, hence my wife's slight admonition).

[David Nicholson]

Cracking job there Tim. Can I just clarify please when planting do you plant into the sandy gravel or plant first and then dress with gravel?

[Tim Ingram]

Both actually David. In the established bed extra plants go into the topdressed sand, whereas I initially plant them into the sharp sand when sections of the bed are made. Watering soon washes the finer sand down through the gravel.

[astragalus]

Fascinating to see the different (and successful) methods gardeners use.  I've used sand beds for years, but they are mounded rather than flat.  The sand has a lot of "fines", which are the small gravels that are screened out for mason's sand, which must be uniform.  When it rains, the fine grains are washed down with the "fines" on top.  People think it's gravel, but all you have to do is brush the "fines" with your havd and you would see it's sand.  The sand beds range from 2' to 4' deep, and the base is rock.  They are not watered except new plants.  It has been successful for many dryland plants which don't usually want to grow in the northeast.  Hope you will add more photos in the spring.
p.s.  I'm awed by your sharp edging line.

[Tim Ingram]

Anne - really interesting to hear that your sand beds are so deep. I was hugely stimulated by seeing pictures of the Kelaidis's front garden, just taken over by 'berms' and with so many incredible plants. I have rather a long way to go to emulate this (and have a rather annoying interest in many other plants too so my garden lacks the dedication that many alpine growers have). I have always been fascinated by dryland plants of all sorts. I don't know how often NARGS members with similar interests visit the UK, but it would be great to organise a conference for AGS and other gardeners on these plants and ways of growing them. This style of gardening, and the wide range of plants that people grow, might have a broader appeal amongst keen gardeners than alpines alone (I think of gardeners like Beth Chatto who has had such a huge influence on so many of us).

[fermi de Sousa]

Tim,
I'd be intrerested in that conference! Maybe something to suggest for Alpines 2021 in Scotland!
We use sandbeds in our garden to grow some of the Aussie plants from Western Australia that demand the extra drainage, but I'm also trying out Juno and Aril iris to see if they can stay dry enough that way over the summer even if we get a downpour.
cheers
fermi