May Allotment Jobs

What’s Possible in May 

May is one of the busiest months on the allotment calendar. The weather is warmer, early sowings may be ready to harvest, and there are new seeds to sow and young plants to plant out. If the month is warm and dry, watering becomes more important, alongside regular weeding and general maintenance.

For young and vulnerable plants, hand-weed carefully to avoid damage and thin out seedlings where they may have been sown too close together. Some crops may still need protection from wet weather, a late frost, or pests and diseases, which are all worth watching for during this month.

The potatoes you planted in April will need to be earthed up in May. When the foliage is approximately 10-12 inches tall, mound soil from each side of the row to nearly cover the plant and form a ridge. This helps protect the tubers from late frosts and prevents them from turning green and inedible.

Hopefully you can also begin enjoying some early harvests from previous sowings, including lettuce, cabbage, spinach, radishes and more.

Indoor-sown seedlings can now be hardened off and planted into their final growing positions. There is also time for more direct sowing, along with continuous sowing of crops for a steady yield. This is helpful if you’re planning what vegetables to grow in May for ongoing harvests.

May is also suitable for planting out early, such as leeks, sprouts and summer cabbage. Leek seedlings should resemble a pencil in size. Make a 6-inch-deep hole with a pole or a similar tool, place the seedling inside, and fill the hole with water. There is no need to fill in the hole with soil, as this will settle naturally.

Watering needs may increase during a warm May, so it is worth checking that you have enough supply in place. Rainwater collection, such as using a water butt, can help reduce reliance on mains water during dry spells.

Keeping on top of weeds is essential this month. Hoeing small weeds early prevents them from becoming established and competing with younger crops for light and nutrients. Some weeds, like bindweed, spread quickly if not controlled properly, and can soon smother growing plants. This can make it harder for you to manage what to plant in May in affected beds.

Slugs and snails are also very active in May. So, when you’re deciding what seeds to plant in May outdoors, ensure that covering them with the right materials is part of the plan, as fresh growth is particularly vulnerable at this stage.

May Allotment Jobs Checklist

May is an important month for getting crops settled into their final positions and keeping your growing schedule on track. Alongside planting and sowing, regular care helps avoid major issues later in the season. Here are the main jobs to focus on this month:

Preparing Beds for New Crops

As soil temperature rises, beds become more active and ready to support strong root growth. This is an ideal time to remove remaining weeds and break up surface compaction to prepare growing spaces for new crops.

While light cultivation is necessary to keep the soil functional, avoid digging if the ground is too dry or compacted. Adding compost or well-rotted organic matter improves the ground’s structure and supports healthy growth as you decide what to plant in May.

Moving Seedlings Into Position

Many crops can now be sown directly outdoors, while seedlings started earlier under cover are ready to be moved into beds. Before planting them outside, harden off young plants by placing them in a sunny position during the day and bringing them back under cover at night.

It’s important to space out your crops at this stage, as overcrowded plants struggle to develop fully and are more prone to diseases. Careful planning helps make the most of your growing space when deciding what to sow in May and which areas are best for transplanting.

Watering & Mulching

With warmer days, soil can dry out quickly, especially in raised beds and containers. Water deeply and less often to encourage strong root systems rather than shallow growth.

Additionally, liquid feeds can be useful for fast-growing crops, while compost added earlier continues to release nutrients slowly. Mulch also plays an important role by holding moisture in the soil and reducing the need for frequent watering, which is helpful when managing vegetables to grow in May across different parts of the plot.

Keeping an Eye Out for Pests & Diseases

Pests become more active in May and can damage young plants quickly if left unchecked. If you have newly planted seedlings in your allotment, bear in mind that slugs, birds and insects are common problems at this time of the year.

Check crops regularly and use physical barriers, like fleece or netting, to keep your plants safe from insects. Removing damaged leaves and monitoring plant health also helps prevent diseases from spreading. While you focus on what seeds to plant in May and where to place them, it’s equally important to take preventative measures for pests and diseases.

May Calendar for Allotment Growers

• May 1st-10th: Start planting out hardened-off seedlings and assess beds for further sowing.

• May 11th-20th: Add support where growth is picking up and mulch soil that is drying out.

• May 21st-31st: Maintain steady watering and begin harvest early, fast-growing crops.

What to Sow Now vs What to Plant in May

If you’re planning what to sow in May, soil temperatures are usually high enough for many crops to go straight into the ground. This is a good time to use empty beds left by early harvests and ensure continued growth throughout the season. Seeds that suit direct sowing outdoors in May include:

• Beetroot
• Carrots
• French beans
• Runner beans
• Courgettes
• Sweetcorn
• Salad leaves

Salad crops benefit from regular succession sowings, so you can keep harvesting without gaps. This approach works well if you’re deciding what vegetables to grow in May for steady use rather than one large crop at once.

If you’re thinking about the best plants to grow in May under cover, you can grow:

• Cucumber
• Squash
• Pumpkins
• Basil

May is also suitable for planting young plants into prepared ground. These are some options that settle well at this point in the growing season:

• Leeks
• Summer brassicas, such as cabbage and sprouts
• Onion sets (if not already planted)

You can also add flowers and herbs that support pollinators and help control pests on the plot.

By mixing direct sowing with planting out young crops, you can keep your beds productive and make the most of the growing conditions that May offers.

Growing Vegetables in Containers or Small Spaces

If you’re still waiting for an allotment, or if space is limited at home, containers let you keep growing without needing full beds. Warmer conditions in May support quicker growth, though pots dry out faster and need more attention.

Here are some great vegetables to grow in May in containers or small spaces:

• Lettuce: Compact types suit pots and window boxes placed in a bright and sheltered spot.

• Radish: Quick to mature and easy to grow in small containers.

• Beetroot: Needs deeper pots, so roots can develop evenly in warm compost.

• Salad Leaves: Grow well in shallow troughs and can be picked regularly as new leaves form.

• Dwarf Peas: Grow well in containers with some shelter from wind.

• Tomatoes: Establish well in pots kept in a greenhouse or sheltered space.

Precautions for Container and Indoor Growing in May

• Move containers into partial shade during hot spells to prevent compost from drying too quickly.
• Keep greenhouse and indoor spaces well-ventilated to reduce the risk of mildew and pests.
• Rotate pots regularly so plants grow evenly and do not lean in one specific direction.
• Check drainage in case of heavy rain, as pots can become waterlogged even in warm weather.

Your May Grow-Your-Own Starter Kit

May is when growth speeds up, and beds begin to fill quickly, so it helps to stay organised and plan what goes where. If you’re choosing a vegetable to grow in May or deciding on the best plants to plant in May, this checklist will help you stay on track:

• Sow quick crops into any gaps left by early harvests to keep beds productive.
• Plant out hardened-off seedlings into prepared soil once nights stay mild.
• Keep fleece handy for sudden temperature drops that can still affect young plants.
• Add compost around established crops to support growth and improve moisture retention.
• Set up supports for climbing plants before they start to lose shape or structure.
• Check water butts and hoses regularly to ensure watering remains consistent as temperatures rise.
• Keep seed trays and pots clean to keep sowing without delays.

Common Problems & How to Avoid Them

Since May enables faster growth, problems can develop quickly if they aren’t spotted early. Being aware of common issues helps you protect crops and make confident choices about the best plants to plant in May as the season moves into full swing.

Dry Soil & Uneven Watering

With more sunshine than usual, the soil in your containers and raised beds can dry out faster than expected. It is important to water thoroughly to ensure that moisture reaches the roots. You can also consider mulching to reduce evaporation and keep conditions more stable.

Pest Pressure on Young Seedlings

Pests are more active now and can damage new leaves overnight. Check plants regularly and use barriers to prevent pests from spreading across your plot.

Overcrowding

Rapid growth can quickly lead to plants competing for light and nutrients. Thin seedlings where needed and avoid planting too closely, particularly when you’re deciding what bulbs to plant in May and placing them near existing crops.

Wind Stress on Tall Plants

Stronger spring winds can bend stems and loosen newly planted roots, making it important to add supporting structures early and firm soil around young plants. This reduces the movement of plants until they’re well-established.

Tools & Techniques for May Success

Before finalising what to plant this month, it helps to have a few essentials ready, so you can respond quickly to changing conditions. These tools include:

• Mulch or compost
• Plant supports and ties
• Slug traps/deterrents
• Hand fork
• Fine netting
• Watering can

Start Your Allotment Growing Journey and Share Your Experience with the Community

May is when your plots start coming to life, with steady growth and plenty of chances to get involved. At Allotment Online, we’re here to support your growing journey with practical advice and shared experience, and our community is always ready to help as you plan your next steps for the months ahead.

Do you have a story you want to share about your growing experience? Share your stories, photos and advice with us in our comments and socials. 

Our website offers insightful strategies for allotment growers. If you are excited to start on your allotment journey, you can check our directory for the nearest allotment association near you.

FAQs for May Allotments

What vegetables can I grow in May on an allotment?

Many crops grow well around this time of the year, including beetroot, carrots, peas, beans, sweetcorn and brassicas planted earlier.

What seeds should I sow outdoors in May?

Direct sowing suits crops like carrots, French beans, radish and salad leaves. Just ensure that the soil temperature stays warm.

What vegetables grow well in containers in May?

Lettuce, radish, dwarf peas and beetroot all do well in pots during May, as long as they’re watered consistently.

What plants can I grow in May under cover?

Cucumbers, basil, squash and pumpkins benefit from the extra warmth of a greenhouse or other sheltered spaces before you transplant them outdoors.