10 Essential Gardening Tasks For May

4 May 2024, written by Benedict Vanheems

Can you believe how quickly spring is racing along? I’m sure gardening turns us into time travellers! This will be another busy month in the garden, planting summer garden favourites and harvesting the first salads of the season, and tending to beans. But first it’s time to earth up our spuds…

1. Earth Up Potatoes

Nothing says summer’s coming more than the stunning, lush foliage – or haulms – of potatoes! But it’s important to keep the developing tubers covered at all costs because they’ll turn green and poisonous if the light gets to them. For determinate potatoes, which form their tubers in one layer in the soil near the surface, mulching works well. Use any type of organic matter for this. I have plenty of grass clippings at this time of year so they will do the job nicely - and they’re free, which is a nice bonus!

For indeterminate varieties, which form tubers at different levels in the soil, earthing up is the way to go. Draw up the soil around the foliage to create ridges into which more spuds can form. Repeat this in few weeks if you can, or just add mulch.

Fava beans — A simple stringline support is enough to keep broad beans up off the ground

2. Support Broad Beans

Broad beans grown in a block will for the most part support each other up as they grow, but the plants at the edge of the block can flop over. When this happens the stems can get broken and the pods end up on the soil where they could rot or be eaten by slugs, and we don’t want that! To avoid this, just push a cane into each corner of the block of plants, and then a couple more along each side. Tie some garden string to one of the canes about one foot (30cm) high, and run it horizontally to the rest. Then add a second string another foot above that.

Just tuck the stems back inside the stringlines if they grow out from it, and that should keep plants up off the ground and stop them flopping about, which will make them a lot easier to pick.

One more tip when growing these beans is to pinch out the growing points – the very top of the stems – once the plants are in full flower. This will make the plants a lot less attractive to black bean aphids, and you can eat the pinched-out tops in salads or enjoy them lightly steamed or sauteed, just like spinach.

Tomato hornworm — Hand-picking is one of the most effective ways to combat pests

3. Check for Pests

Late spring to early summer is when many pests put in their first appearance. As well as aphids of just about any type, there are whitefly, flea beetles, asparagus beetles, sawflies…to name just a few!

Inspect plants regularly and act at the very first sign of a pest. Hand-pick pest caterpillars, squash aphids with your fingers or blast them off with a jet of water. Keep plants well-watered so they’re as healthy as they can be, which will make them more able to withstand the odd nibble.

Row covers of horticultural fleece or insect mesh are your friends. Use them to cover particularly susceptible crops like carrots to protect them from carrot fly, or radishes, to keep the flea beetles away.

Ben with a broccoli stalk mustache — Cut up thick stalks to make composting quicker. Or don't if, like Ben, you quite fancy a moustache

4. Clear Overwintered Crops

With summer looming, it’s time to dig up tired old winter crops like sprouting broccoli and Brussels sprouts and throw them on the compost heap. They’ve served you well, but the time has come to make way for replacements that will start cropping in a few more weeks. For instance I’ll be digging out my broccoli and replanting with a few courgettes, coupled with some nasturtiums to give a splash of colour and tempt in the bees.

Many overwintered brassicas and other crops have thick stems that take ages to rot down in the compost heap, but you can help them break down quicker by first chopping them up with a sharp spade or loppers.

Aubergine — If you didn't sow warm-season crops like this aubergine earlier in the year, catch up by ordering young plants

5. Order Plants

There’s nothing wrong with buying in ready-to-go young vegetable plants. If you’re really busy or don’t have much protected space to raise lots of warm-season seedlings, ordering in plants can be a lifesaver.

Remove any packaging as soon as you can – don’t delay. Inspect them for any signs of pests or diseases. If the plants are dry, give them a good soaking. If they’re really dry, plonk them into a bucket of water for at least 10 minutes to re-wet the rootball. Then get on and either plant them into their final positions, or pot them on to a bigger container if their growing areas aren’t quite ready or if the weather isn’t suitable for planting yet.

6. Plant Up a Straw Bale Bed

If you can get your hands on straw bales, they’re definitely worth considering. Bales bring up plants closer to waist level, which means less bending and a convenient height for tending your crops. They’re arguably easier to manage than containers because their sizeable volume acts like a sponge, soaking up and holding onto moisture for longer, so you can get away with watering a lot less often.

Bales can be picked up fairly cheaply and they’re easy to prepare – or condition – ready for planting. But don’t delay, because you’ll need to crack on with all this as soon as possible so they’re ready to plant into in good time. Watch our step-by-step straw bale video to find out how to do it.

Courgette plant — Mound soil around courgette plants to avoid water wastage

7. Plant Courgettes

Now is a good time to get your warm-season vegetables like courgettes into place. Acclimatise them to outdoor conditions over the course of about a week by leaving them outdoors for progressively longer times. If the weather is set to be fair for the coming week, you can take that as a green light to finish planting.

Don’t be tempted to plant them too closely together. They may seem lost with lots of space between them but, believe me, they’ll soon put on dramatic growth. By summer they’ll be dominating the space with great big leaves and, we hope, fistfuls of dense, nutty fruits.

Because they grow so big, so fast, they need really fertile soil – ideally already fertilised with compost or well-rotted manure – to power them on. Dig out a nice big hole then mix in a few handfuls of a balanced organic fertiliser such as chicken manure pellets for extra oomph.

Burying a bottomless, upturned bottle into the soil near the plant is a good way to help hold onto water and deliver it where it’s needed, to the roots – you just fill this to the brim at watering time and walk away. But I know lots of us are concerned about microplastics in the soil, so seeing as the ground here is nice and level, I’m going for a different tack this summer.

You can trap water around each plant by banking up a little levee of soil all the way around it. Water into it, and the water should have time to soak through evenly to the roots without washing away across the surface or evaporating.

Salad leaves — Start picking salad leaves as soon as they are big enough

8. Harvest Your First Salad Crops

Even this early in the season, there’s a good chance you may be cutting your first salads of the season. What a treat it is to have a salad bowl-ready flush of loveliness!

If you haven’t yet started salad crops off, there’s still plenty of time. You can make repeat sowings every few weeks to keep the freshness coming. At this time of year you can sow direct, perhaps using a salad leaf mix, or you can start seeds off in plug trays or pots if the spot where you want them to grow is going to be occupied by something else for another few weeks.

All salads respond well to regular watering in dry weather, especially if it’s hot. Watch out for slugs – keep surrounding areas clear of both weeds and long grass to remove hiding places, and consider setting up beer traps towards the edge of the plot to lure slugs away from susceptible plants.

Hoeing — Hoe regularly and weeds will be a non-issue

9. Weeding Made Easy

Weeds are sneaky little so-and-sos! Don’t let them take advantage of your good-natured patience – show no mercy – keep on top of them! I’ve said it before, and I’m sure I’ll say it again, but a few minutes every week to lightly hoe or hand-weed really pays off.

Keep the soil moving with a hoe, and weeds won’t get a chance to even think about making an appearance. Do this on a warm, sunny, slightly breezy day if you can – this way any weeds you do slice off or pull up will quickly shrivel up on the soil surface and disappear back into it. If there isn’t enough space to hoe between plants, get down onto your haunches and hand-weed – as I say, a few minutes each week should keep top things under control.

It’s really important to weed regularly in spring. Weed growth tends to slow down from summer – but only if you’ve been diligent with weeding up until that point! It’s reassuring to know that the onslaught of weeds will ease off before too long.

Keep your hoe working as efficiently as possible by running a sharpening stone across the blade from time to time, at the same angle as the blade. Doing this every so often ensures weeds are effortlessly sliced off at soil level, like a steaming-hot knife through butter!

Sweetcorn seeds — Sow sweet corn indoors, or direct outside if it's warm enough

10. Sow Sweet Corn

This is the ideal time of year to sow corn of all types, either direct, or into plug trays, pots or even toilet paper tubes to start in the warm then plant out towards the end of the month. In my somewhat cool climate (equivalent to zone 8) getting an indoor start really helps.

I’ve chosen a sweet variety of corn this summer, as always, and I’m already dreaming of those outrageously indulgent cobs. I serve mine with a curl of butter and lots of pepper – let me know how you prefer them in the comments below.

If you’d like to know my method for starting off this true winner of the summer garden, check out our latest sowing video which you’ll find, for your convenience, right here!