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Forget me nots

Gardening jobs for May

At last! We’re getting to the point where we should soon be over the danger from frost, and safe to plant out all those tender plants you’ve been sheltering in greenhouses and on windowsills for the past few weeks and months!

Before you do, its worth going through a process of ‘hardening off’ the plants – basically getting them used to their new conditions.

Plants on a garden table

Hardening off involves taking young plants outside during the day, and bringing them back in at night.

So if they’ve been on a sunny windowsill sit them outside in the daytime and keep in an unheated greenhouse at night (or bring them back inside if you don’t have one). Do this for a few weeks and they’ll be more used to fluctuating temperatures and standing up to wind and rain before you plant them out for good. The RHS has more advice on hardening off here.

So, what other jobs are there to do in the garden in May?

Plant out your sweet peas

Planting out sweet peas

If you’ve been growing sweet peas, you can now transplant those seedlings into their final positions. You can also sow some straight from seed now, just make sure your young plants or seedlings have something to climb up! Use a cane or a trellis and they’ll soon find their way up!

Keep watering and feeding

Hanging basket of petunias being watered with a watering can

Don’t forget to keep an eye on plants in pots to make sure they don’t dry out. It’s so easy to forget, but your containers can dry up alarmingly quickly otherwise! Get into a habit of adding a feed to the watering can once a week and you’ll be giving them a boost of energy, too. To save on your water consumption, why not fit a water butt, if you don’t have one already? They’re surprisingly easy to install, and collect a lot of rainwater which is really beneficial for your plants, too.

Deadhead your spring bulbs once they’ve finished flowering

Fading daffodils in a spring display

As your spring bulbs start to fade, it’s ok to remove the sad looking flowers. You can do this for tulips, daffodils, hyacinths and lilies. But do this job carefully – you need to remove only the flowering part but keep the leaves in place to die back naturally. This allows them to continue to feed goodness into the bulb so that they’ll return strongly next year. In our garden, we’re very impatient to tidy up the leftover leaves of spring bulbs when they’re finished, so I’ll usually dig up daffodils and tulips and repot them into a container whilst they die down. Come autumn I then get all the bulbs out of the container and replant them into the borders. But you can skip out this work and just leave them where they are – removing the leaves once they’re really turned yellow and their work is done.

Plant out your dahlias

Dahlias emerging from tubers in a container

I love dahlias. And they’re really easy to grow – simply pop a tuber in a tub or into the ground and hey presto – beautiful flowers all through summer until first frosts.

You may have started off your dahlia tubers in tubs and want to plant them into their final position this month. Be sure that no frost is forecast, and then go for it!

If you didn’t start dahlias from tubers, no worries. There are so many varieties to choose from in local nurseries and garden centres right now. Choose your favourites and add them to the garden. If you overwinter them, they’ll come back every year. A brilliant investment.

Earth up your potatoes to get a good crop

Earthing up potatoes being grown in bags

Earthing up potatoes.


If you’re growing potatoes, make sure you keep ‘earthing them’ – basically topping up the soil to keep covering over any green shoots that start to appear. I usually grow my potatoes in grow bags… and it’s surprising how quickly the green shoots keep coming. But I earth the bags up until they’re almost full and leave it at that.

Keep an eye out for pests

red lily beetle on the green lily leaves

If, like me, your garden plays host to a large number of slimy slugs, try some environmentally friendly prevention measures – such as  beer traps (literally dig a hole, add a small container, fill with beer… they are attracted by the smell, fall in and drown), or use nematodes, which are a biological control (far better than a pesticide).

You can also just get out there first thing in the morning or last thing at night, when slugs are most active, and round up the little blighters!

If snails are your problem – try an evening patrol, especially when the weather is wet.

You should also keep a vigilant eye out for Lily Beetles (above) and their larvae on emerging lilies, or rosemary and viburnum plants. If you spot them – remove and destroy them – they’re a non-native species and will literally destroy the plants!

It’s a great time to sow lots of salad!

Two small containers of salad leaves growing in a garden

These are my cut & come again salad leaves, grown in just these little containers and enough to keep me in salads for some time!

Salad leaves will now grow really well – and some varieties are super quick, too. I like regularly sowing batches of rocket and ‘cut and come again’ salad leaves, which should keep me in salad all summer!

Overrun with Forget Me Nots?


Forget me nots

I’ve noticed lots of gardens locally have incredible displays of lovely Forget Me Nots. They look really gorgeous in swathes across the garden, especially when in their full blue glory!

But they are prolific self-seeders and they can spread much more than you intend. So this month is a good time to pull some of these plants up to control their numbers. You should be able to just pull them out by hand – no digging required. Leave a few behind and they’ll happily multiply so you’ll still have plenty of plants again come next spring.

About the author:

My name is Gemma. I’m the editor of Lowton & Golborne News and a very keen but amateur gardener. I mainly enjoy growing flowers in my garden in Golborne, and I’m also experimenting with edibles, too. You can follow my garden on Instagram @gandtgarden.

What jobs will you be doing in the garden this month?

We’d love to hear from you in the comments below!

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