How to grow sweetcorn – an easy beginner’s guide

grow sweetcorn

Sweetcorn is a universally enjoyed vegetable that is a tasty and nutritious addition to any meal. It can be eaten both cold and hot. It’s ideal as one of your 5-a-day, plus it’s easy to grow sweetcorn.


There are plenty of health benefits to sweetcorn. It’s is cholesterol-free and is a good source of vitamin C and A, potassium, and fibre. It’s also very high in antioxidants.


Sweetcorn is a 100% whole grain vegetable that is high in natural sugars/starches. Here’s how to grow sweetcorn in your vegetable patch.



Interesting sweetcorn facts!

Sweetcorn leaves were used as chewing gum by Native Americans.


Corn is grown on every continent except Antarctica.


Baby sweetcorn is produced from regular corn plants that are harvested early, while the ears are immature.


Corn is great for eating but also has so many other uses including medicinal.


There is one strand of silk for each kernel on a cob.



When to Plant

Sweetcorn has a fairly long growing period, so it’s important to get it planted toward the end of March to ensure it’s ready to eat during the summer.


To successfully germination, the soil temperature needs to be above 16°C. You can always use a black plastic cover to increase the soil’s temperature. Plant seeds through holes in the plastic.


You can always extend the harvest by planting more seeds a couple of weeks after the first round.



planting corn



Soil considerations

To grow sweetcorn successfully, you need to pay attention to the soil as they can be quite picky about it. So it’s worth spending some time preparing your soil to ensure the best results. A few weeks before planting, it’s a good idea to work in well-rotted manure or compost into the soil.


Your soil should drain well yet retain some moisture as sweetcorn needs a lot of water to grow effectively.


As corn plants are pollinated by wind, you should avoid planting in rows. Instead, plants of blocks of at least four rows deeps. This increases the chance of producing viable ears.



Sweetcorn varieties

Many sweetcorn varieties are available and most are easy to grow. The RHS recommends these four:


‘Swift’ F1

(Extra tender sweet) One of the best varieties to grow in your garden with plenty of cobs.


‘Golden Giant’ AGM

(Supersweet) A vigorous main season variety with large, good quality cobs.


‘Lark’ AGM

(Extra tender sweet) Early and high yielding with sweet, tender, top quality cobs.


‘Earlibird’ AGM

(Supersweet) Vigorous plants with good sized, uniform cobs. Early cropping.



Gardening centres should stock a range of these and many other varieties. If you prefer to shop online, we recommended buying from Dobies, who offer a fantastic range of vegetable seeds.



Planting sweetcorn

You can grow sweetcorn both indoors and outside. However, it’s not recommended to start seeds indoors and then transplant. So decide on a position based on your climate and variety.


Sow seeds around 4 cm deep into the soil and roughly 10 cm apart. You should space rows about 80 cm apart. It’s then worth fertilizing and watering to aid the rapid grow.



harvesting sweetcorn



How to nurture sweetcorn

As corn has shallow roots, it’s easy to damage them when weeding. It’s best to mulch with organic matter to conserve moisture and suppress weeds. You’ll also need to water regularly to ensure your plants keep growing.


When your plants grow to around 10 cm, thin them so they are around 25 cm apart and have enough room to keep developing.


Encourage the pollination of the female flower by tapping the top of the plants when the male flowers (tassels) open. Poor pollination results in sparsely filled cobs.



Harvesting sweetcorn

When tassels begin to brown and cobs start to swell, then they are ripe for harvesting. Husks should feel plump when squeezed, and the kernels will burst with a light milky liquid when pressed.


However, if a creamy white liquid appears, you’ve left them too long and you should remove ears from the stalk right away. Overripe sweetcorn will taste starchy.


If the kernels burst open with a clear liquid, then they still need more time to develop before they are ready for harvesting.


To harvest, simply grab an ear with one hand, and hold the stalk with the other. Pull the corn down and away while rotating until it breaks free of the stalk.



How to store fresh sweetcorn

As sweetcorn begins to lose it sweetness soon after harvesting, it’s best to use them within a few days of picking.


Sweetcorn also freezes well, especially if you remove the ears before freezing. By freezing some of your crop, you can enjoy eating sweetcorn throughout the year.



sweetcorn ears



Common pests and problems

A problem if you grow sweetcorn is pests. And sadly, corn attracts a range of pests and animals who will all happily snack on your crop! You’ll also need to look out for any diseases and treat or remote bad plants to stop the spread.


Mice and rats

They will munch seeds but can be stopped by placing traps around the area where you’ve planted the seeds. If you’re not big on trapping mice or rats then plant something sacrificial which will deter them from munching on your sweetcorn!


Slugs and snails

Feeding on young seedlings, slugs and snails leave a slime trail both on the soil and leaves. Thankfully, there are plenty of ways to control slugs and snails including eggshell barriers, copper tape and sawdust.



Causing a range of problems, birds can eat seedlings, buds and even the corn itself. Bird-scaring mechanisms can provide relief for a while but the best way to protect your plants is covering them with horticultural fleece or mesh.



That’s how to grow sweetcorn!

As a highly useful vegetable, it’s easy to grow sweetcorn and ensure you have plentiful supply all year round. Plus by growing your own, you cut down your food miles, benefiting the planet.


If you’re looking to expand your vegetable patch, consider planting potatoes or trying to grow carrots, they are fairly easy to grow and always supply an abundant harvest! So that’s how to grow sweetcorn in your garden!