May is when spring turns into early summer. It's hard to keep up with all the plants that are bursting into flower – look out for irises, peonies, columbines and hardy geraniums. By the end of the month the first shrub roses will be in bloom. May weather is often very changeable. Gardeners may have to contend with everything from frost and strong winds, to heatwaves and thunderstorms. With lawns to care for and summer containers to plan and plant, you'll probably need to stock up on composts, plant foods and lawn treatments. Choose from the wide range of J Arthur Bower's products to help you create a summer garden to be proud of.

ESSENTIAL JOBS CHECKLIST FOR MAY

• Mow your lawn regularly, feed it, and treat weeds and moss
• Create new lawns with seed or turves
• Clip fast-growing hedges and feed them
• Fix supports around tall perennials
• Pot on summer bedding and harden it off
• Plant up hanging baskets but keep them in a greenhouse
• Feed roses and spray them where pests and diseases are a problem
• Trim spring-flowering rock plants
• Start to plant grow-bags
• Sow biennials, annual flowers, herbs and vegetables
• Feed fruit

Sow annual flowers

• Fix supports around tall and floppy perennials before they get too tall. There's a wide range of ready-made supports in garden centres now, or you can use twiggy sticks
• Biennials are plants that are sown one year to flower the next. Examples include wallflowers, Canterbury bells, sweet williams, forget-me-nots, foxgloves and honesty. Seeds of all these plants should be sown this month. You can sow them out of doors in a well-prepared seed bed before transplanting to their final flowering position in the autumn.
• If you've been growing your own summer bedding the young plants should be ready now for hardening off – in other words acclimatising them to a life outdoors after being coddled under glass. To start with put the young plants out in the daytime only. Towards the end of the month they can be left out all the time. Remember that J Arthur Bower's compost contain enough feed to last for 6-8 weeks. After that time is up you'll need to start with a liquid feed.
• You can start to plant up hanging baskets and other summer containers, but if you can keep them in a greenhouse or porch for a couple of weeks before putting them out this will help them get established. Choose J Arthur Bower's special Hanging Basket and Container Compost, which contains vermiculite and water storing granules to increase the water-holding capacity. You'll need to start feeding your baskets and tubs after 4-6 weeks with J Arthur Bower's Hanging Basket and Container liquid plant food. Alternatively, use J Arthur Bower's Once plant food as you plant up the containers. Once contains enough food to last the plants for the whole growing season. If you prefer to mix your own compost for summer tubs you can buy J Arthur Bower's Quenchers water-storing granules separately.

• Keep a close eye on your roses and spray at the first sign of pests or disease. When buying new roses you may prefer to choose some of the newest hybrids bred for their resistance to pests and diseases

• If you applied your first lawn weed early you should feed again towards the end of the month with J Arthur Bower's Spring and Summer Lawn Food
• Treat weeds as necessary

• Fuchsias and pelargoniums should be growing strongly now. Fuchsias should be pinched out once they reach about five inches (12.5 cm) high. This will help make them bushy and far more flowers will be produced.
• Cannas and other tender exotics will probably need potting on into larger pots now. Use J Arthur Bower's Seed and Potting compost for best results and keep the plants well watered.
• Grow-bags are an easy way to grow a wide range of tender vegetables, including tomatoes, cucumbers, aubergines, peppers and even melons. Bring the bags into the greenhouse a weeks or so before planting into them – this will give the compost time to warm up first. J Arthur Bower produces peat and peat-free grow-bags.

• Summer containers can be planted up this month. If you don't have a greenhouse or porch to keep them away from late frosts, just make sure you listen to the weather forecast and cover the containers with fleece if necessary.

• Be ready to cover potatoes if frost is forecast
• Sow outdoor marrows and courgettes at the end of the month. Start preparing the planting site at the beginning of the month by digging holes one foot deep and wide, about three feet apart. Dig plenty of J Arthur Bower's Organic Farmyard Manure into each hole then mound the earth up over the manure.
• Runner beans can be sown in the second half of the month on a site prepared earlier.
• In warmer parts of the country why not try sweetcorn – it should be sown at the end of the month.

• Take cuttings of rosemary, sage and thyme from the previous years growth. Take off the lower leaves of the cuttings and put them round the edge of a pot filled either with J Arthur Bower's Perlite or Sharp Sand.
• If you haven't got a space for a herb garden, many herbs can be successfully grown in containers. Chives, mint and parsley enjoy quite a rich soil and would be better in J Arthur Bower's John Innes No. 2. For marjoram, thyme, sage, hyssop, rosemary and lavender mix 3 parts John Innes No. 1 with 1 part J Arthur Bower's sharp sand and add some coarse grit. Annual herbs such as coriander and chervil can be grown in the same mixture or in multi-purpose compost.

• Apply a general plant food around fruit trees unless they have failed to set much fruit. Young trees may still need watering in dry weather
• Gooseberry and blackcurrant bushes can also be fed

• All types of water plants can be planted this month using J Arthur Bower's Aquatic Compost. Top dress the basket with gravel to stop compost clouding the water
• Algae and blanketweed may become a problem as the weather warms up, especially in fairly new ponds where there is not much leaf cover on the surface. It's easy to remove blanketweed with a stick – you'll find you can wind it round and pull it out. If algae persist you might consider using a proprietary pond treatment, but be sure to follow the instructions carefully and use the correct amount for your pond.

• Trim back aubrietas and arabis that have flowered – this helps keep them compact and free-flowering.. After pruning feed the plants with an all-round plant food such as J Arthur Bower's Growmore or Fish, Blood and Bone
• May's a good month to plant new alpines. Dig out a hole bigger than the rootball and half fill with a gritty planting mixture. Mix this into the surrounding soil and add more mixture around the plant. Water in well and top dress with J Arthur Bower's coarse grit.

Look at our information pages. The aim is to cut out the mystique that surrounds many common tasks, and to explain in a simple way, why and how to do them. This way, we hope to help you enjoy your garden more, and get the best out of it.

Under each topic, you'll also find a guide to the wide range of J Arthur Bower's products available to help you with that particular task. The choice is yours.