Sarah Milne's gardening tips for April

April can be a wet month … as the saying goes April showers bring May flowers so it’s a good time to think about water supply and usage in your garden - not just from a sustainable and environmental perspective but also from a cost consideration as water meters become the norm.

So, thrifty tip for the month is … conserve water and harvest the rain. Rainwater isn’t just free, it’s also better for your plants. If you have space and a downpipe from guttering then get a water butt. There are a number of schemes around the UK offering free or subsidised water butts so check with your local council first before you buy one. Alternatively, you could use an old dustbin with taps and converter kits readily available from DIY retailers. Uncovered water butts will be a magnet for mosquito larvae, so make sure you keep you water supply covered.Finding creative ways to reuse water will really make a difference. In addition to using grey water from washing up or taking a bath or shower, you can collect and use cooking water. Simply remove whatever you were cooking, let the water cool to room temperature and then use it in the garden. It can also double up as a plant supplement as nutrients that leach during cooking from vegetables and eggs enhance the water.

When watering plants – especially in containers or around newly planted trees and shrubs – try to avoid any wastage by getting water right into the soil. An easy way to do this is to recycle a 1-litre plastic bottle. Unscrew and discard the top, cut off the base of the bottle, and then push it lid end down into the soil. Once deep enough so it doesn’t fall over, fill the bottle with water and it will drip water gradually where it is needed the most direct to the plant roots.

As garden soil gets wetter and warmer, now is the ideal time to sow your favourite annual herbs for a summer supply says the RHS (Royal Horticultural Society). Sow seeds of parsley, basil and chives in seed trays or individual modules and place on a sunny windowsill. You can now start to sow coriander, dill and chervil direct into the ground and Mediterranean herbs such as rosemary or oregano can be planted outside this month in free-draining soil.

Rosemary is such a versatile herb providing evergreen interest all year round, fragrant leaves for use in cooking and nectar-rich flowers for bees in spring. It thrives in a sunny, sheltered spot in well-drained soil and also grows well in containers but may need to be potted on every couple of years. There are a number of different varieties to choose from including … ‘Tuscan Blue' one of the best for topiaries - with dense blue-green foliage it’s highly fragrant and grows four feet tall; 'Prostratus' is great for planting in window boxes because it cascades down; and ‘Majorca Pink’ produces pink flowers in spring/summer and is highly aromatic.

The RHS Gardener’s Checklist for April ….

Plant hardy container-grown trees and shrubs

Prune hardy Fuchsia back to healthy buds

Sow sweet peas outside

Prune winter stems such as Cornus and Salix

Look out for pests on new shoots

Sow hardy vegetables such as carrots and beetroot outside

Plant out chitted potatoes

Watch out for late frosts

Check hedges and shrubs for birds’ nests before pruning

Keep bird feeders clean to help prevent diseases spreading