Diarmuid Gavin: From lawn care to seed sowing, the eight spring garden tasks you should be tackling now

While the days are getting brighter and longer, frost can still pose a threat to tender plants. Keep an eye on weather forecasts and be prepared to protect vulnerable specimens with horticultural fleece or cloches during cold spells, especially in the evenings. Meanwhile, there are plenty of tasks to be getting on with in the garden.

1. Prepare the soil

Begin by preparing your soil for the upcoming planting season. If the ground isn’t waterlogged or frozen, you can start digging over beds and borders, removing any weeds and debris. Incorporating organic matter such as compost or well-rotted manure helps to feed soil and improve its structure. Apply a layer of mulch around plants to conserve soil moisture, suppress weeds and regulate soil temperature as the weather warms up.

2. Sow seeds

March marks the perfect time to sow seeds indoors for vegetables like tomatoes, peppers and cucumbers. Use heated propagators or warm windowsills to provide the necessary warmth for germination. You can also sow hardy vegetable seeds directly outdoors, including peas, spinach, lettuce, and radishes. Hardy annual flowers can also be sown directly outdoors or started off indoors before transplanting them outdoors. St Patrick’s Day is the traditional date to get your spuds in the ground.

3. Prune and train

Take advantage of the dormant period to prune deciduous trees and shrubs before they burst into growth. Remove dead, damaged or crossing branches to promote healthy growth and shape the plant. It’s also an ideal time to train climbing roses and other climbers, guiding them along supports or trellises. Shrubs grown for colourful stems such as Cornus and salix can be cut back hard to promote fresh stems. Summer-flowering shrubs, such as fuchsia, spiraea, perovskia, lavatera and buddleja, usually flower on new growth, so a good chop now will produce more flowers later.

4. Divide perennials

Many perennial plants benefit from division every few years to maintain vigour and prevent overcrowding. March provides an excellent window for dividing plants like hostas and herbaceous perennials. Replant the divisions promptly, ensuring they have sufficient space and nutrients to thrive. When lifting and dividing perennials, take the opportunity to get rid of any invasive weeds tangled in their roots or in the soil. Spring-flowering plants are best divided in autumn. Put supports in for perennial plants that require them — if you put them in now, the plants will grow over them and disguise them. Twigs such as birch make excellent frames for perennials and climbers to cover.

5. Prepare for lawn care

March signals the start of the lawn care season. Begin by raking away any debris and moss that has accumulated over the winter months. If conditions allow, consider aerating the lawn to improve drainage and promote healthy root growth. The first cut of the year is done with blades higher than usual. Sharpen turf borders with a half-moon lawn edger and clip edges with lawn clippers.

6. Tend to bulbs

As early spring bulbs like daffodils and crocuses blossom, ensure they receive adequate moisture and nutrients to support their growth, particularly if you are growing them in containers and pots. Deadhead spent flowers to divert energy back into the bulb and allow the foliage to die back naturally.

7. Plant bare-root trees and shrubs

March is the last chance to plant bare-root trees, shrubs and hedging plants before they come into leaf. Ensure the soil is well-prepared and water newly planted specimens thoroughly.

8. Plan and prepare

Take the time to plan your garden layout, make a list of plants you’d like to add, and order seeds or plants as needed. Start thinking about any new projects or improvements you’d like to make in your garden throughout the coming months.

Plant of the week

Dahlias Pick up some dahlia tubers from your local garden centre or supermarket this month and get them started in a frost-free place over the next two months. You will then have plants ready to go outdoors once the frost has finished and you will be enjoying beautiful displays from summer to late autumn. ‘Chat Noir’ is a semi-cactus variety with rich red petals and dark maroon centre. Long stems and good vase life make this an excellent variety to grow for cut flowers.

Reader Q&A

I’d like to plant a rosemary hedge – is that OK to grow here? Grainne

Yes, rosemary grows well here — it’s hardy and evergreen. That said, it’s a Mediterranean plant which enjoys full sun and well-drained soil and will struggle in cold, water-logged soil. It’s a great choice as a hedge with its fragrant foliage and lovely nectar-rich blue flowers in early summer which are attractive to bees. I’d recommend ‘Mrs Jessop’s’, which is an upright variety so best for a hedging scenario.

Submit your gardening questions to Diarmuid via his Instagram @diarmuidgavin using the hashtag #weekendgarden