Gardening with Mary: it’s blooming time – best spring gardening tips

Since the start of February, the days have been steadily growing longer and the weariness of winter has at last begun to fade.

Around our garden, hellebores are reaching their peak of bloom, presenting their astonishing diversity of colours and forms.

I love them for their incredible resilience and long flowering, and their flowers provide essential early nectar for pollinators. Once established, they come back every year and are very easy to care for, thriving in shady borders or woodland areas with well-drained, nutrient-rich soil. At the start of the year we prune away the old leaves to give the new buds plenty of light and air.

Our snowdrops are nearly over and once the flowers have died back, while the foliage is still green and active, we will give them a feed with a diluted liquid seaweed fertiliser for quick absorption to boost the bulbs energy for next year’s display. If you want to increase the expanse of your snowdrop colonies, now is also a good time to lift and divide them.

Simply dig up a clump, split it into smaller clumps of 3-5 plants, and replant these immediately wherever you have gaps.

This is the perfect time to prepare for the upcoming growing season by pruning, dividing perennial plants as their new growth emerges, nourishing your soil, transplanting bare root plants, starting seeds indoors, sharpening garden tools and clearing away plant debris to help minimise issues with pests and diseases.

However, if your ground is still sodden after the interminable rains, don’t be in too much of a hurry as trampling wet soil can cause severe compaction and be harmful to its structure.

If you have to walk in wet areas of your garden, put down wooden planks or boards to create temporary paths, especially for accessing beds and borders or crossing lawns.

A great wet day job is cleaning the outside of your polytunnel or greenhouse to remove any buildup of grime and algae. It’s important to clean your polytunnel at least once a year, ideally before the start of the growing season to ensure your plants get all the light they need to grow and prolong the life of the polythene cover.

A rainy day is ideal as the rain helps to loosen up the layer of dirt before using a soft brush to clean it down. Having nervously watched me, too many times, balancing precariously on all sorts of makeshift platforms, my husband bought me a flow-through truck wash brush with a telescopic handle that extends to 3m a few years back.

It has transformed this operation. The water travels up through the hollow, telescopic handle from an attached garden hose and directly into the brush head. If necessary, before washing, you can apply a gentle, non-toxic cleaner, like Citrox (citrus-based), that’s safe for use around plants.

You can prune roses now too. The old advice about waiting until 17 March is no longer correct, as our increasingly milder winters means growth is starting earlier and will be advancing strongly by then. Nowadays, I aim to have my rose pruning completed by 14 February. There is a lot of mystique about rose pruning that can make the task seem daunting.

Resilient roses

However, roses are resilient – pruning is not about perfection. It’s about balancing the shape and structure of the plant, removing what no longer serves it, enhancing air circulation to reduce risk of fungal diseases and making space for new growth that will yield a generous display.

It helps to know what type of rose you are pruning. Floribundas, hybrid teas and hybrid perpetuals should be cut back hard now, to around 25-30cm above the ground. Begin by removing any dead, diseased, damaged, spindly and crossing stems and then prune the remaining stems to form an open bowl of short, outward-facing branches.

Always cut just above an outward-facing bud. Shrub roses need very little pruning except to reduce overly long, straggly growth and remove dead or crossing stems. Climbers are best pruned in autumn, removing a third of the plant to encourage new growth in spring while rambling roses are pruned after flowering in later summer.

We are hosting a family wedding in our garden at the end of August. What can we grow, that is quite easy, to give our borders a boost of colour for this time? – Nuala, Co Kerry.

I suggest you grow hardy and half-hardy annuals which should be in flower from mid to late summer onwards and which will be easy to cultivate. You can sow seeds of hardy annuals directly where you want them to flower in late April or early May.

Sow the seeds thinly in rows 15-20cm apart, in well-prepared soil, and thin the seedlings to about 13cm apart. Your choice of plants might include calendula, Centaurea cyanus, nigella or love-in-a-mist, Scabiosa atropurpurea, godetia and Ammi majus.

You can also sow seeds of half-hardy annuals indoors under gentle heat in March.

Prick out seedlings into seed trays and harden them off for transplanting outdoors after frosts. Alternatively, buy annuals as young plants and plant them outside in late May.

Cut back: clumps of deciduous ornamental grasses, like miscanthus and calamagrostis should be cut back hard now to the ground before the new green shoots grow too long. However, they should not be moved or lifted and divided until they are actively growing.

Get digging: if lots of ‘onesies’ or single perennials of a kind are dominating your garden, dig up and divide the plants just as their new growth is emerging and replant the divisions in groups to create drifts of each variety for greater impact.

Borders: mulch borders with a thick (7-10cm) layer of compost or well-rotted manure spread over the soil surface to give nourishment through the growing season ahead.

Mary Keenan and Ross Doyle run Gash Gardens, Co Laois. See gashgardens.ie