A favourite of nectar-collecting bees, this perennial is available in a wide range of shades
When I am asked to recommend a long-flowering perennial, penstemon is one of my top picks. Its tall spires of bell-shaped flowers look a bit like a foxglove, and when foxgloves start to go to seed around early July, penstemons pick up the baton and flower away until late autumn. It’s related to the foxglove, and bees love to burrow away for nectar in the tubular flowers.
Also known as beardtongues, penstemons hail, in the main, from the United States. Enthusiasts over there are called Penstemaniacs, and they gather every year to spot penstemons growing wild in their native habitats.
On this side of the pond, European plant breeders have created many hybrids and new cultivars, and the range of flower colour is wide. From fiery reds to electric blues, raspberry ripple pinks and lavender to rich purples, there is a penstemon for every colour scheme.
‘Heavenly Blue’ has gorgeous summer sky-blue flowers with a hint of pink inside. ‘Raven’ is a velvety deep-plum colour, and ‘Garnet’ a popular bright-crimson variety. Softer colours such as pink-and-white combos are available, such as the very pretty ‘Apple Blossom’. ‘Sour Grapes’ is a lovely purple, or you might just prefer a simple white variety.
There are some alpine varieties, which are suitable for rockeries, but in general, they are best-suited to floral borders as well as garden pots, forming bushy shrub shapes. They are semi-evergreen, but if you have very cold winters, it’s worth protecting the roots with a good mulch.
I leave them over-winter and cut back in April. They can look a bit messy by the end of summer when they start to collapse a bit, but I think it’s best to leave them as is. If you prune hard at this stage, you will get tender growth that won’t survive a harsh winter.
You can take cuttings in summer to propagate as insurance. They propagate well from cuttings — mid-to-late summer is the best time to do this. Pick a healthy, non-flowering shoot and cut below a leaf pair. Remove leaves from the cutting, leaving just one pair, and get it into your cuttings compost as soon as you can.
If you like to grow from seed, check out seedaholic.com’s selection called Twizzle. These are available in coral, purple, scarlet, white and blue, and have taller stems and less foliage than your customary penstemon.
Plant in full or partial sunshine in moist but well-drained soil. They are quite drought tolerant but don’t like the crown or their roots to sit in soggy soil.
For instant colour, plant some penstemons today and you’ll be enjoying their blooms until the first frost. Deadheading will help prolong the flowering period, and you can also remove finished flower stalks from the base and you may get a second, albeit smaller, spike of fresh flowers.
Lavender tolerates neglect and will do well on a poor soil. It needs an open, sunny position and a hard cutting-back. My advice would be to change the plant every five years or so. French lavenders are real eye candy with their fancy ‘ears’. Full of flamboyant blooms in May and June, they will repeat flower if pruned after the first flowering, but they are not as tough as English lavender. If you want traditional lavender, then you’ll need English lavender with its wonderful scent, hardiness and neat habit. This type will last many years longer than the French one.
I recently bought two miniature rose bushes. One is doing fine and has bloomed, but the other one has a lot of foliage on it, but covered in a white powdery-like substance. Could you please tell me the reason for this, and how to treat it?
Your rose has a fungus called powdery mildew. This is often associated with roses that are weak in some form or are grown in shady or poorly ventilated areas. Prevention is more effective than cure — choose disease-resistant roses, keep well fed and watered at the roots, and grow in an open, sunny position. To cure, you will need to remove all the diseased foliage. Put it in the bin, not on a compost heap, as you don’t want the fungal spores infecting anything else. You can also try a homemade spray of baking powder in water with a teaspoon of washing-up liquid.
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