My first post is of some text I prepared late in 2011 for the RHS in the form of a question and answer session in which I aimed cover some sensible Snowdrop issues……
Q. Should snowdrops be planted in the green, or as dry bulbs?
A. Traditionally snowdrops have been sold and planted in the green. This means you can see the flower you are buying, and check it has been correctly identified.
But there are drawbacks: plants sold in the green are often freshly dug, and haven’t benefitted from proper establishment after potting the previous autumn. Also, when digging plants grown in the open, roots can be severed, causing a check in growth.
The annual growth cycle of bulbs moved in the green is far from over: as the foliage dies back in early summer, starch drains back into the bulb, fattening it ready for next year’s performance. With this in mind it’s important to water ‘in the green’ snowdrops as soon as they are planted to re-establish root contact with the soil.
This doesn’t apply to bulbs bought and planted in their dormant state. Happily there is a shift in this direction, especially by sellers who pot-grow snowdrops for the full three-year cycle. The resulting fat bulbs are sent out in late summer. It takes a little imagination to plant at this time of year, but at least you can choose your planting spot while any herbaceous neighbours can be seen above ground.
Q. What sort of growing conditions do snowdrops prefer?
A. Here at The Garden House, where we have a relatively wet climate, I tend to choose a planting position underneath a deciduous tree or shrub which soaks up any excess moisture from the soil when bulbs are dormant. Snowdrop bulbs underground are unlikely to dry out as they would when left around in the potting shed. Those gardening in drier areas need to bother less about such constraints!
Almost without exception snowdrops tolerate most soil types provided they are not water-logged. Don’t believe everything you hear about snowdrops doing best in neutral to alkaline soils – here the pH is about 5.5 – and they do just fine.
They can be grown in pots but this is only recommended for people with plenty of experience growing a wide range of bulbs in containers. Potted snowdrops should always be plunged, and protected from the worst of the weather. This is not a comment on hardiness – all snowdrops are hardy and can, with a little care, be grown in the open garden.
Q. Which companion plants would you recommend for growing with snowdrops?
A. It’s easier to answer the question ‘what shouldn’t I grow with snowdrops?’ I avoid dense evergreen woody plants – they often come with mats of roots that can out-compete small bulbs and deprive them of light.
It’s sensible to avoid siting snowdrops (or other small bulbs) near plants with travelling rhizomes that can smother out neighbours in just a single season. This rules out many geraniums, Symphytum, spreading clumpers like pulmonarias – and choose your epimediums with care!
Good bedfellows for snowdrops are tightly clumping woodlanders like trilliums, Gillenia and crown-forming ferns (such as cultivars of Athyrium filix-femina, Dryopteris affinis, Polystichum setiferum and Asplenium scolopendrium). Hostas are excellent as they do a great job of covering the ground left bare by spring bulbaceous plantings.
In open, perennial-based borders, snowdrops can be incorporated around long-term stalwarts that don’t need regular division. Although I tend not to plant next to classic herbaceous border plants like Aster, Hemerocallis, Helenium or Phlox, I would use them around peonies, baptisias, Actaea simplex forms and larger herbaceous sedums.
Q. What are the best snowdrops for: a) scent and b) interesting/unusual markings or colours?
Most snowdrops are scented to some degree. Especially notable is ‘Ginns’, which has a fragrance like bitter almonds. You can smell an established clump from several metres away, especially on a warm day. Autumnal G. reginae-olgae ‘Cambridge’ smells of wallflowers.
Snowdrops with unusual markings, especially on the outer segments, are currently a huge cult with collectors and the most prized snowdrops tend to be those with the boldest markings. These variations can be arrestingly beautiful, which goes a long way to explaining why some snowdrop cultivars are so sought after!
Until recently coloured snowdrops were mostly restricted to a few G. plicatus and G. nivalis cultivars with yellow inner markings and ovaries. Today, not only has this colour appeared in other species, but it has been joined by exciting soft oranges and pinks (although it’s likely to be a long time before they make it into any of the specialist sellers’ lists).
Q. What care/maintenance tips can you share?
The general rule of thumb is to lift and split snowdrops about every three years. If you are bothered by keel slugs it might pay to surround the bulbs with a handful of gritty sand as a deterrent, especially with new plants.
If you are growing just a few snowdrop cultivars, you are less likely to be bothered by the worst snowdrop ailment, Stagonospora curtisii (the risk of disease increases with each acquisition). Happily there is an awareness among sellers of the disease but if your bulbs arrive with orange or brownish streaks, do return them.
Serious collectors take various measures to manage the problem, such as washing tools between handling different snowdrops cultivars, putting plenty of space between them, and even quarantining new plants before introducing them into the garden.