swiss chard in a vegetable garden

How to Grow Chard

Chard, also called Swiss chard, is a nutritious leafy green that grows best in the cool weather of Spring and Autumn. However, it can tolerate warm and hot weather in the summer, especially if planted slightly shaded, and it can also cope with the cold in the middle of the winter – what a super green! Furthermore, one single plant can keep on producing food for you for 12 months if it’s happy! A few things to note though; when the seedlings are small they can only tolerate a light frost, and if you live in a very cold climate they will need some form of protection in the winter. Your Harvst S-Series Mini-Greenhouse is perfect for that!  

Chard comes in many different colours and varieties. Some are even called Rainbow Chard for a good reason! It is a versatile veg that can be used as a salad green or a leaf vegetable for cooking. The cooking process will make it more tender and milder in flavour.  


Chard is easy to grow from seed and can be sown direct or transplanted later. It is a perfect crop to sow in your S-Series as it can stay in there till it matures or be transplanted outside. It can also be harvested as baby leaves or be left to grow really big in the ground. One sowing can last you a whole year! 

Seeds can be soaked overnight to speed up germination but with the right temperatures in your S-Series, it shouldn’t be necessary. Seed germinates in 5 to 7 days at 16-18°C, but can take up to 3 weeks to germinate if the soil is colder. They tend not to germinate if the soil is colder than 10°C though.

Fill a tray with compost, a general peat free multi-purpose compost will do, as the seeds are quite big and do not need the more expensive seed compost. Water the compost first and then sow the seeds about 2.5cm apart and sprinkle 1cm of compost on top. Press down slightly to make sure that the seeds are in good contact with the compost. Carefully water again. 

Keep the soil evenly moist until seeds germinate because if they dry out they will most likely not germinate at all. This can be aided with a plastic dome over the tray but it’s not a must! However, as a general rule , the colder the soil the less moisture you want, because a cold and very wet growing medium often results in rotten seeds. 

Growing options 

You can choose from one of the growing options below or do a combination of 2, 3 or 4! If you are transplanting to the garden, wait till mid to late Spring after the soil has warmed to at least 10°C.

  1. Baby Leaves: Start harvesting the leaves when they are as big as leaves in a supermarket baby leaf salad bag! If you pick one or two leaves from each plant on the outside, rather than the whole plant, it should keep on growing for a while and give you a few harvests! 
  2. Grow till maturity in your S-Series: When the seedlings have emerged, thin them to 15cm apart. This can be done by cutting the rejects with scissors (eat them in a salad!) or carefully using a stick/pencil to loosen the soil and lift the seedling up by its leaves and transplant to elsewhere. Make sure they are big enough to handle before you set out to do this. The compost will only have enough nutrients for a few weeks so you will have to feed the plants with an organic fertiliser throughout the growing season. 
  3. Plant outside: When the seedlings have developed their true set of leaves (not the first set appearing but the second set) they can be transplanted out into your garden. Space them 20-25cm apart in a staggered pattern or in a row about 35cm apart. If you have problems with slugs or it’s still very cold, you can pot them on and keep them in your S-Series a little longer. A bigger plant can resist a slug attack much better! When planting outside it is best to make sure that your soil is great before planting, by adding well rotten manure or other organic material so that it’s full of nutrients for your plants. If your soil is not great you can feed the plants with an organic fertiliser throughout the growing season. When transplanting seedlings, ideally plant out early morning or evening and/or on an overcast day. Avoid planting at peak sun times or on windy days as this can cause sun or windburn which can lead to death! 
  4. Container Grown Chard: Chard can grow well outside in a container but try to choose one that is 15-20 cm wide and tall. Keep in mind that the compost will only have enough nutrients for a few weeks, so you will have to feed the plants with an organic fertiliser throughout the growing season. 

Generally, chard grows best in full sun but can benefit from some shade if they’re grown in the summer. As a general rule, chard prefers rich, moisture retentive soil with plenty of nutritious compost mixed in, however it will still grow well in any average soil so don’t despair! 


Harvest the outer leaves once they reach your desired size and leave the center leaves to continue growing. Harvest by pulling the leaves off at the base, or pinch off if the plant is still very small. 

Watch out! 

Chard is generally pest free but aphids and leaf miners can attack. Aphids are best rinsed off with water, but if the invasion is large it might be worth also putting them outside for a while to let natural predators such as ladybirds do the job. Leaf miners can best be treated by removing the affected leaves. 

Pro Tip

If the plants have grown too big, cut them back to about 7cm above the ground in late summer – they will produce new leaves for an autumn harvest.

Nerdy facts

The botanical name of Chard is Beta vulgaris var. Cicla  and it belongs to the Chenopodiaceae family. Other members include beets, spinach, quinoa, and sugar beets.

Recommended Chard Varieties

Here are three great varieties, but there are many more fantastic ones to choose from!

  • ‘Lucullus’ is almost lime green with a very mild flavour
  • ‘Bright Lights’ and ‘Rainbow chard’ produce a rainbow of coloured stems with large leaves of green or bronze
  • ‘Fordhook Giant’ is just that, a giant with dark leaves and white stems.