Plant of the Month - July
Intense heat and probably no rain: but there are plants that will still brave the weather and bring colour to the summer garden.
Tall Achillea filipendulina lights up the summer border and self-seeds easily. By contrast, Achillea umbellata is small, spreading ground cover with white flowers early in the season. Also with a creeping habit, Achillea coarctata grows to around 30cm and forms a dense mat and supresses weeds. Achillea are native to the Eastern Mediterranean or the Balkans. There are hybrids in other colours such as rusty red and orange which are useful for the designer’s palette.
Agapanthus is native to South Africa. It has many admirable qualities: blooming in high summer when everything else is starting to look tired; tall flower stalks in clear blue shades that give the flower border a ‘lift’; reasonably drought tolerant and looks good in a pot.
So, what are your Agapanthus looking like at the moment? I hope they are doing better than mine. The photo was taken a few years ago when my Agapanthus were obligingly blooming for me. Since then: nothing. Not a flower. Lots of leaves which last year got mangled by a fungal disease. I have tried feeding them; not feeding them; in pot; in the ground; keeping them dry in winter; bringing them indoors in winter; leaving them alone to survive as best they can. It makes no difference. If any of you has the answer please let me know! Oh and then the badgers came and destroyed the pots.
These delicate little papery flowers on slender stalks are a delight – but sadly the photo doesn’t show their deep blue colour. Native to the Mediterranean, Catananche is highly tolerant of drought and cold. No need to do anything apart from trimming the dead blooms in autumn.
Echinops - Globe thistle
This spiky relative of the thistle is very dramatic in the gravel garden. Native to southern Europe and resistant to drought. Trim back the dry flower stalk in early spring.
Hydrangea quercifolia - Oak leaf hydrangea
Hydrangeas are surprisingly popular in Italy, even though the growing conditions here are totally unsuited as they mostly need moist, acid soil. The Oak leaf variety however seems to cope with a little alkalinity and dry conditions although is best with some shade. I grow this hydrangea in a pot and it is a strong statement in the corner of the terrace. Acid compost is recommended but not essential and there is no need to do anything else. This shrub reaches 1m or a little taller in a pot -no pruning required.
A curious ornamental grass which has these ‘bird’s head’ flowers, grows about 60cm tall and forms a clump. It tolerates clay soil and full sun and complete drought. Native to the Mediterranean. Just tease out dry leaves in early spring - don’t cut it back.
Nerium - Oleander
Where would we be without Oleanders to brighten up sun-soaked days? But not all oleanders are created equal: some are much better at resisting cold than others. A really lovely variety I saw in Tunisia with variegated leaves turns out not to be able to withstand frost at all, whereas the yellow hybrid ‘Luteum plenum’ is supposed to cope with minus 8 degrees. The vivaios around here rarely mention this - the oleanders are usually just sold on the basis of flower colour. Some oleanders are also scented – another feature that is often overlooked. A final consideration with oleanders is that all parts of the plant are toxic and this may be a problem with small children and animals in the garden: it also means that insects are not interested in them. In spring trim a few tall stems down to near the base to keep the shrub compact, otherwise little care is required.
Perovskia - Russian sage
Native to Central Asia, Perovskia is a very useful plant for the dry garden designer: it is resistant to extremes of heat, drought and cold and yet provides a soft feature with its slender stems and sprays of tiny blue flowers. Tall varieties include ‘Blue Spire’ which reaches about 1m. Shorter varieties are also available but I find them less successful. Perovskia starts to bloom in July and keeps going right through September. In winter the bare stems are white and glow in low sunlight.
The culinary herb thyme (Thymus vulgaris) is native to the rocky ‘garrigue’ areas around the Mediterranean and so it is no surprise that it does well in our gardens here. It can however start to get woody if left to its own devices. I find that thyme self-seeds quite readily so it is best to take out the old plants after a few years and let the new ones grow through. There are several other types which are useful and ornamental in the dry garden. I have recently ‘discovered’ Thymus capitatus which has remarkable violet flowers in July. Native to Crete, it has a taller and more upright growth habit (40cm) than ordinary thyme. Low growing Thymus serpyllum and Thymus ciliatus are alternatives to lawn; they do however need a bit more water than ordinary thyme.
Trachelospermum jasminoides - Star Jasmine
Not really a jasmine but who cares - this evergreen climber is invaluable in the summer garden. The little white flowers bring a heady perfume to warm evenings: the scent of Italy, even though this plant is native to China. The stems support themselves by twining around a support; it is very robust and can handle heat, drought and cold, even some shade. In autumn the shiny green foliage takes on a red tinge.
The photo at the top of this page shows Achillea filipendulina self-seeded
Many of these articles first appeared in the Castiglione del Lago monthly newsletter “Qua e là” edited by Priscilla Worsley
All text and photographs © Yvonne Barton unless stated otherwise