Q: Judith Cooper wrote: “We have an area of our garden that is shady and quite dry. At the moment we have bluebells, forget me nots and sweet woodruff there but want something that will flower later in the year, also what plants will thrive under our native hedgerow?”
A: This is a difficult area for colour later in the season. I have a similar spot, and I find day lilies (hemerocallis) flower and spread quite happily. Most hardy geraniums also cope well with dry soil. You often see hostas recommended as bog plants, but they can be grown under much drier conditions, and those varieties with vary pale variegations are actually best grown in some shade, otherwise the cream or white parts of the leaves can burn and turn brown in the sun. If you have room to grow shrubs, hydrangeas will flower without a problem, but they must be watered during drought periods, or flower size will be reduced. Adding plenty of organic material, such as well-rotted farmyard manure or garden compost to the soil will help it to retain moisture, as well as increasing fertility.
Regarding the hedge bottom, you can obtain seed of native hedgerow plants quite readily, but for an instant display, try using our Lawn Flower Seed Mats. These contain annuals, many of them native, that will still flower this summer if used now. Clear any grass or other plants at intervals along the hedge, then spread the mats over the bare earth and water well. Don’t dead-head after flowering, as the plants will set seed and you will find their seedlings springing up all along the hedge bottom next year.
Q: Sam Jones asked: I have several healthy hydrangea bushes, but they never flower, despite being in the garden for around eight years. I always give them a good prune every spring, and they produce lots of shoots, but no flower beds.
A: Hydrangeas produce their flowers at the tips of mature shoots and the previous year’s new growth, so you’re actually cutting off all the buds. If you need to keep the plants a reasonable size, remove about one-third of older branches (evenly spaced) at the base every year; this will keep them more compact, while still giving a good show every summer.
Q: Sam Jones asked: I planted some wallflowers from plugs last autumn. They have produced some flowers, but there are more new shoots than flowering ones. Do I have to pull these up, or can I leave them for next year?
A: Wallflowers are actually short-lived perennial plants, usually grown as biennials (sown one year to flower the next, after which they are replaced). Sometimes wallflowers planted in the autumn have not developed sufficiently to flower well the following spring, and will produce more non-flowering shoots that will flower the year after. Remove the flowered shoots, and you will find those without flowers will bloom in spring 2014, but the plants may be much larger than expected.