THERE is plenty to do in the garden now May is here. The sunshine and showers, together with hoped-for warmer weather, really gets the plants going; before we know it they are filling beds and pots with colour.

One of the top May jobs is hardening off tender plants such as bedding for containers and tender vegetables, such as French and runner beans that were started off indoors last month.

Our French beans have been hardening off for some time now as the garden is so sheltered, but in more exposed areas and frost pockets it’s worth while taking it more slowly.

Day and night-time fluctuations in temperature can affect the growth of tender plants quite significantly, so start them off by putting them outside for only a couple of hours in the first few days.

Extend the period over the rest of the month until they can only be brought in at night. For the final few days leave them outside the whole time then plant out.

It’s worth keeping an eye on the forecast for the first few days after planting out; should the worst happen and we get a warning for an early June frost, protect tender specimens with fleece.

Hardier plants such as sweet peas can be toughened up more quickly. Ones started off indoors in February will be getting big now and can have their tops pinched out if this hasn’t been done already, and be put outside during the day for a week or so.

If they look healthy, extend the period to include the night and then plant into their flowering spot sometime during this month. Sweet peas can stand quite low temperatures, although they will need to be protected from frost.

If, like me, you didn’t get around to sowing sweet peas, pots of seedlings can be found in most garden centres and on market stalls. I bought a pot for £1 on York market a couple of weeks ago in which there were 20 little plants, a bargain. So many plants in a small space get overcrowded very quickly, so last weekend the empty toilet roll tubes that had been collecting on the windowsill were finally put to use.

These are perfect for growing on sweet peas. Simply slot the rolls into an old margarine container, six will fit perfectly into a 1kg tub, fill with compost, make a hole for the seedling to drop into and firm in.

Sweet peas have long roots even when small and they appreciate having the space to develop a strong system. They can be left in a sheltered spot outside to grow on for while before being planted out into their flowering position.

Don’t worry about taking the plants out of their tubes, the whole thing can be put into the soil where the cardboard will gradually break down.

This year I have resolved to grow a few vegetables in spaces in the flower bed. We don’t have a lot of room but I noticed a few gaps last year which are being filled with edible plants rather than flowers this time.

Broad beans are in, with French beans and sprouts waiting in the wings. They will go in towards the end of the month.

Some of the sprouts have already been destroyed by slugs, so I want to keep an eye on them and grow them into good size plants before they take their chance in the garden.

Annoyingly, the one courgette plant has also been eaten by a slimy something, so I will have to start again.

Rhododendron walk

RHS Garden Harlow Carr is celebrating its rhododendrons this weekend with specialist walks, displays and an opportunity to meet the experts in this family of plants.

The Rhododendrons In Bloom walks will be held today and tomorrow at 11am and 2pm and will give an insight into these floriferous shrubs and their place in the history of Harlow Carr.

Places on the walks need to be booked by phoning 0845 612 1253. Tickets are £5 for RHS members and £12 for non-members. The tickets include admission to the garden.

There is plenty to see at Harlow Carr as spring gets into its stride. Normal entry fee to the garden is free for RHS members (plus one guest).

For non-members the cost is adults £7, children six to 16 £2.50 and children under six free.

Gardening TV and radio

Tomorrow.

8am, BBC Radio Humberside, The Great Outdoors. With Blair Jacobs and Doug Stewart.

9am, BBC Radio Leeds, Tim Crowther and Joe Maiden.

2pm, BBC R4, Gardeners’ Question Time. Matthew Biggs, Bob Flowerdew, Anne Swithinbank and chairman Eric Robson help members of Herrington Flower Club in Sunderland with their gardening problems. The gardening weather forecast is at 2.40pm.

Wednesday.

8pm, BBC2, The Edible Garden. Alys Fowler comes to the end of her series with a look at the winter larder. Squash, kale and Jerusalem artichokes will all provide sustenance in the leaner months.

Friday.

3pm, BBC R4, Gardeners’ Question Time. Peter Gibbs, Carole Baxter, Bob Flowerdew and Anne Swithinbank are in Aboyne in Aberdeenshire. Bob also shows how to make up lost time in the veg plot and the gardening forecast is at 3.40pm. (Repeated on Sunday).

8.30pm, BBC2, Gardeners’ World. Toby Buckland prepares the hanging baskets, Joe looks at getting style into the borders and Carol discusses the spurge family.

Open gardens

Wednesday.

In aid of the National Gardens Scheme.

24, Redbank Road, off Whitcliffe Lane, Ripon. Small garden planted for year-round interest with raised beds, rockeries and gravel containing a wide range of perennials, alpines, shrubs and species peony some of which have been grown from seed. Open 2pm-5pm. Admission £2.