Step out onto any suburban street from mid June to early July and the pervading scent will be that of lime tree blossom. I do not mean the citrus limes whose juice graces a Mojito cocktail. I’m referring to the flowers which, when dried, become the ’tilleul’ infusion popular in France. Before it became a familiar high street brand, no day trip to Calais or Boulogne was complete without a visit to L’Occitane to buy the delicately perfumed lime flower soap. These last couple of weeks the lime trees have been at the height of their intoxicating power, pumping forth the freshly sweet perfume which to me epitomises early summer.
Close examination reveals that the yellow green clusters hanging below the heart-shaped leaves of Tilia cordata (Small-leaved lime) and the roundly oval leaves of Tilia platyphyllos (Broad-leaved lime) consist of downward facing bunches of four or five stems. These are attached to a wing-shaped bract which aids seed dispersal and each stem terminates in a cluster of yellow pollen-tipped stamens surrounded by five outer sepals, the central core of each of which ripens into a small spherical fruit. The fruit or ‘nutlet’ as I have read it is called, is covered in fine down lending them a whitish grey appearance.
On warm days, lime tree flowers attract many pollinators, and an odd phenomenon has been observed with the Silver leaved lime, Tilia tomentosa, which is pollinated by honeybees. The trees’ nectar appears to have a narcotic effect on the bees, with dead or dying bees found under the trees each year. A team at Royal Botanic Gardens, Kew is investigating the issue and there is an interesting article on the Kew website entitled ‘Do Lime trees kill bees?’
I haven’t reported recently upon my Friday stints as a member of the team of garden volunteers at the National Trust’s Osterley Park. For the past two Fridays we have concentrated our efforts in the Tudor Walled Garden, preparing it for its annual colourful impact in late summer and early autumn. In fact, thanks to a myriad of self-sown poppies, two of the quadrant beds have exploded into sheets of mauve, pink and red. In the bed where the green manure was sown earlier this year, (see my blog from this March, Rolling along within the walls), the crimson clover blends beautifully with the poppies.
Last week, in the bed closest to the gate leading to the gardener’s bothy, we planted a mixture of four Gladioli cultivars: Roma, Indian summer, Espresso and Purple Flora. I’m looking forward to seeing their blend of colours later this summer. Meanwhile, our colleague Tracey has worked tirelessly to sow, plant and harvest produce on the third bed. Where possible the rest of the team help her with weeding and some planting, as well as harvesting early crops for the coach house cafe. A gentle job I was assigned last week involved deadheading the sweet peas which grow up obelisks at the corner of the plots, the variety this year being ‘Beaujolais’. Removing the seed pods which develop so swiftly after the flowers have faded encourages more flowers by preventing the plant from expending energy on seed production.
Whilst weeding the edge of one of the plots we found two self-sown members of the Nightshade family, Solanaceae, to which potatoes, tomatoes and aubergines belong. The pioneers we found are the Shoofly plant, Nicandra physaloides, and the Thornapple, Datura stramonium. We left the former in place as its pretty mauve flowers are attractive but the latter will be removed as it doesn’t form part of the planting scheme as well as being poisonous.
This Friday saw us working on the five round beds alongside the wall which divides the Tudor Walled Garden from the picking garden (which is bursting with colourful flowers at the moment). A small fruit tree is planted in the centre of each round bed, and is underplanted for spring and early summer impact with Doronicum, Irises, Papaver somniferum (Opium poppies) and Love in a Mist (Nigella damascena). Sadly the plants have finished flowering and our task was to remove the poppies and Nigella (both annuals) and to reduce the iris leaves by 2/3rds and cut their flower stalks to ground level. We had an hour left in the afternoon to begin a similar task on the long border of the Tudor Walled Garden where a repeating planting scheme of Salvias, honey scented Honey spurge (Euphorbia mellifera), Plume poppy (Macleaya macrocarpa) and Foxtail lily, (Eremurus), is bestowed a sprinkling of gold dust by the shimmering stems and flowers of Elephant grass (Stipa gigantea).
Thinking of taller plants growing through lower growing plants, in my own garden I’ve been admiring the delicate yet long lasting flowers of Chinese meadow rue, Thalictrum delavayi, for about three weeks. At a height of about two metres they hover gracefully above the nearby Astrantia major ‘Abbey Road’, a burgundy Heuchera and Houttynia cordata. Like the small leaved lime mentioned above, another plant named for its heart-shaped leaves.
I grew forty cultivars of citrus in the early 1990s, but have never grown a single lime tree of this sort. They only started to get planted as street trees in about 2000, but never became popular. I am not certain if they can even be found in nurseries here anymore. I find them compelling because they are so unfamiliar.
Very interesting to read about the lime tree and bees. Makes me glad that I don’t have one nearby as I’m trying to make my garden as bee-friendly as possible.