Lots of plants are reaching their summer peak now, and our borders are full of colour and texture. By now, most of our perennial plants have knitted together nicely to create weed-suppressing blankets, which makes maintenance a little less demanding. Some plants that are particularly thriving and looking splendid in July include agapanthus, roses, dierama, astilbes, crocosmias and echinops. There is still plenty to be done in the garden, but in much less of a hurry than in spring and early summer. Through July and August, our focus is on keeping plants well-groomed so that they stay in their prime for as long as possible.
Philadelphus ‘Virginal’. \ Mary Keenan
Regular deadheading to remove faded blooms and removing browned stems from perennials is one of the best ways of extending summer colour in flower borders. Not only will plants look fresh and tidier, but it will also trick the plants into channelling their energy away from seed production and into forming additional flowers instead. Depending on the type of plant you are deadheading, either use a sharp pair of secateurs or flower snips or use your finger to pinch out the spent flower heads. Cut just above the first set of healthy leaves, below the spent flower. Repeat-flowering roses that are regularly deadheaded will also be encouraged to flower again, but if your rose has beautiful ornamental hips, do not deadhead. Rose stems that have completely finished their first flush of blooms should have the faded flower head- and the stem beneath it- cut back to the first outward-facing leaf with five leaflets.
Philadelphus ‘Virginal’. \ Mary Keenan
Early-flowering perennials, such as oriental poppies, centaurea or perennial cornflower, symphytum, pulmonaria, aquilegia, nepeta and hardy geraniums are cut back hard now too if they look untidy or have become covered in mildew — they will quickly produce neat mounds of fresh foliage and, sometimes, another flush of flowers. If you have any empty spaces in borders, why not fill them with new herbaceous plants or, if you were thinking ahead, with lilies that were planted in pots in spring for the purpose and now ready to flower.
We also make sure that tall plants are kept well supported in case of a surprise thundery downpour. Herbaceous borders are particularly vulnerable to the domino effect of one plant collapsing on top of another during wind or heavy rain. If that happens and borders are a little messy, keeping their edges smart and neatly defined will help make everything look so much better.
A steady weeding routine is also ongoing throughout the summer season to remove weeds before they have a chance to go to seed and create a new generation. It also ensures that garden plants are not competing for valuable resources like nutrients and water.
Apart from that, July is a month when we try to make time to enjoy the results of all the hard work. While you take pleasure in your own garden, don’t forget that July is also the perfect opportunity to visit other gardens.
Cut back hardy geraniums
Most hardy geraniums begin flowering in May and June and by now the foliage of some varieties, such as the Geranium pratense, G. phaeum and G. x oxonianum cultivars, has begun to look tatty, their long-spent flower stems have collapsed and are sprawling into neighbouring plants and their middles have become sparse. If you have not already done so, take a pair of shears to them now and you’ll find the plants respond by producing a fresh crop of attractive, more compact foliage, followed sometimes by sporadic reblooming, depending on variety.
Straggly growth of Geranium x oxonianum ‘Winscombe’ in the process of being cut back to promote fresh, compact growth. \ Mary Keenan
Cut the stems right down to within 5-8cm of the ground. It seems a bit drastic, and the plant will look a little bare for a while, but within a few days it’ll start to recover. Certain long-flowering varieties like ‘Rozanne’ and low-growing, mound-forming varieties like ‘Russell Prichard’ should not be cut now as they stay compact and keep flowering. Give trimmed plants a thorough soaking and apply a general purpose liquid feed to boost recovery.
Timely Reminder: Prune philadelphus
The wonderful smelling philadelphus, or mock-orange flowers, are going over now and this shrub is best pruned immediately after flowering. It’s not vital every year, but it does promote better flowering. Pruning now enables the new growth to get established this year in order to produce flowers in the next. Simply prune all stems that have just flowered to around a third of their length, cutting just above a set of buds. To rejuvenate established shrubs and prevent leggy growth, you can also thin out from the base a few of the older stems, cutting about one in four stems back to almost ground level, doing it in such a way as to preserve or improve the overall shape, and get rid of the oldest, thickest stems. You might need stronger loppers or a pruning saw, rather than secateurs. Other shrubs that flower in early summer on wood formed the year before, such as weigela, kolkwitzia and deutzia, should also be trimmed when blooms fade.
Saturday and Sunday 8 and 9 July 2023:
Plant Fair at Irish National Stud and Gardens, Tully, Co Kildare in association with Irish Specialist Nursery Association and gardening talks. More information: irishnationalstud.ie
Saturday 22 July:
Belvedere Gardens Plant Fair. Time: 11am to 5pm. Venue: Belvedere House and Gardens, Mullingar, Co Westmeath. Specialist plant nurseries and talks by Jimi Blake and Paul Smyth.
Sunday 30 July:
Open Weekend at Gortnalee Gardens, Donaghmore, Co Laois R32C8K0. Time: 2pm to 5pm. Refreshments available. No admission fee but donations for Laois Hospice welcome.
Saturday 29 July to Sunday 5 August:
Carlow Garden Festival. Venue: Gardens and garden centres along the Carlow Garden Trail. A week-long programme of events with a tempting line-up of 18 acclaimed gardeners, garden experts and garden designers from Ireland and the UK. More information: www.carlowgardentrail.com.
Sunday 6 August: Farmleigh Plant Fair.
Time: 10am to 5pm. Venue: Farmleigh Estate, Phoenix Park, Dublin. Specialist plant nurseries and other stalls selling garden-related items. Gardening talks and floral art demonstrations during the day.
Mary Keenan and Ross Doyle run Gash Gardens, Co. Laois open to the public. www.gashgardens.ie
This Month’s To-Do List
Once flowering has finished, tidy up the vigorous growth of rambling roses by removing one in three of the oldest stems, that have flowered or are supporting a network of tangled growth, entirely at or near ground level. Then prune all side shoots back by about two thirds.Water new trees, shrubs and perennials planted in spring, using grey water wherever possible, to help them through dry spells. Apply the water to the soil around the base of plants rather than the foliage. Remember that a rain shower, even a heavy and prolonged one, will not be enough if the ground is dry and hard.Keep water levels in ponds topped up during hot spells to ensure the health of plants and fish, and to prevent damage to the pond liner.
Lots of plants are reaching their summer peak now, and our borders are full of colour and texture. By now, most of our perennial plants have knitted together nicely to create weed-suppressing blankets, which makes maintenance a little less demanding. Some plants that are particularly thriving and looking splendid in July include agapanthus, roses, dierama, astilbes, crocosmias and echinops. There is still plenty to be done in the garden, but in much less of a hurry than in spring and early summer. Through July and August, our focus is on keeping plants well-groomed so that they stay in their prime for as long as possible.
Philadelphus ‘Virginal’. \ Mary Keenan
Regular deadheading to remove faded blooms and removing browned stems from perennials is one of the best ways of extending summer colour in flower borders. Not only will plants look fresh and tidier, but it will also trick the plants into channelling their energy away from seed production and into forming additional flowers instead. Depending on the type of plant you are deadheading, either use a sharp pair of secateurs or flower snips or use your finger to pinch out the spent flower heads. Cut just above the first set of healthy leaves, below the spent flower. Repeat-flowering roses that are regularly deadheaded will also be encouraged to flower again, but if your rose has beautiful ornamental hips, do not deadhead. Rose stems that have completely finished their first flush of blooms should have the faded flower head- and the stem beneath it- cut back to the first outward-facing leaf with five leaflets.
Philadelphus ‘Virginal’. \ Mary Keenan
Early-flowering perennials, such as oriental poppies, centaurea or perennial cornflower, symphytum, pulmonaria, aquilegia, nepeta and hardy geraniums are cut back hard now too if they look untidy or have become covered in mildew — they will quickly produce neat mounds of fresh foliage and, sometimes, another flush of flowers. If you have any empty spaces in borders, why not fill them with new herbaceous plants or, if you were thinking ahead, with lilies that were planted in pots in spring for the purpose and now ready to flower.
We also make sure that tall plants are kept well supported in case of a surprise thundery downpour. Herbaceous borders are particularly vulnerable to the domino effect of one plant collapsing on top of another during wind or heavy rain. If that happens and borders are a little messy, keeping their edges smart and neatly defined will help make everything look so much better.
A steady weeding routine is also ongoing throughout the summer season to remove weeds before they have a chance to go to seed and create a new generation. It also ensures that garden plants are not competing for valuable resources like nutrients and water.
Apart from that, July is a month when we try to make time to enjoy the results of all the hard work. While you take pleasure in your own garden, don’t forget that July is also the perfect opportunity to visit other gardens.
Cut back hardy geraniums
Most hardy geraniums begin flowering in May and June and by now the foliage of some varieties, such as the Geranium pratense, G. phaeum and G. x oxonianum cultivars, has begun to look tatty, their long-spent flower stems have collapsed and are sprawling into neighbouring plants and their middles have become sparse. If you have not already done so, take a pair of shears to them now and you’ll find the plants respond by producing a fresh crop of attractive, more compact foliage, followed sometimes by sporadic reblooming, depending on variety.
Straggly growth of Geranium x oxonianum ‘Winscombe’ in the process of being cut back to promote fresh, compact growth. \ Mary Keenan
Cut the stems right down to within 5-8cm of the ground. It seems a bit drastic, and the plant will look a little bare for a while, but within a few days it’ll start to recover. Certain long-flowering varieties like ‘Rozanne’ and low-growing, mound-forming varieties like ‘Russell Prichard’ should not be cut now as they stay compact and keep flowering. Give trimmed plants a thorough soaking and apply a general purpose liquid feed to boost recovery.
Timely Reminder: Prune philadelphus
The wonderful smelling philadelphus, or mock-orange flowers, are going over now and this shrub is best pruned immediately after flowering. It’s not vital every year, but it does promote better flowering. Pruning now enables the new growth to get established this year in order to produce flowers in the next. Simply prune all stems that have just flowered to around a third of their length, cutting just above a set of buds. To rejuvenate established shrubs and prevent leggy growth, you can also thin out from the base a few of the older stems, cutting about one in four stems back to almost ground level, doing it in such a way as to preserve or improve the overall shape, and get rid of the oldest, thickest stems. You might need stronger loppers or a pruning saw, rather than secateurs. Other shrubs that flower in early summer on wood formed the year before, such as weigela, kolkwitzia and deutzia, should also be trimmed when blooms fade.
Saturday and Sunday 8 and 9 July 2023:
Plant Fair at Irish National Stud and Gardens, Tully, Co Kildare in association with Irish Specialist Nursery Association and gardening talks. More information: irishnationalstud.ie
Saturday 22 July:
Belvedere Gardens Plant Fair. Time: 11am to 5pm. Venue: Belvedere House and Gardens, Mullingar, Co Westmeath. Specialist plant nurseries and talks by Jimi Blake and Paul Smyth.
Sunday 30 July:
Open Weekend at Gortnalee Gardens, Donaghmore, Co Laois R32C8K0. Time: 2pm to 5pm. Refreshments available. No admission fee but donations for Laois Hospice welcome.
Saturday 29 July to Sunday 5 August:
Carlow Garden Festival. Venue: Gardens and garden centres along the Carlow Garden Trail. A week-long programme of events with a tempting line-up of 18 acclaimed gardeners, garden experts and garden designers from Ireland and the UK. More information: www.carlowgardentrail.com.
Sunday 6 August: Farmleigh Plant Fair.
Time: 10am to 5pm. Venue: Farmleigh Estate, Phoenix Park, Dublin. Specialist plant nurseries and other stalls selling garden-related items. Gardening talks and floral art demonstrations during the day.
Mary Keenan and Ross Doyle run Gash Gardens, Co. Laois open to the public. www.gashgardens.ie
This Month’s To-Do List
Once flowering has finished, tidy up the vigorous growth of rambling roses by removing one in three of the oldest stems, that have flowered or are supporting a network of tangled growth, entirely at or near ground level. Then prune all side shoots back by about two thirds.Water new trees, shrubs and perennials planted in spring, using grey water wherever possible, to help them through dry spells. Apply the water to the soil around the base of plants rather than the foliage. Remember that a rain shower, even a heavy and prolonged one, will not be enough if the ground is dry and hard.Keep water levels in ponds topped up during hot spells to ensure the health of plants and fish, and to prevent damage to the pond liner. 
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