Growing Basil – grow from seeds

Lots of large green leaves on small plants growing in a green rectangle tub. growing basil on a windowsill

Growing basil is very rewarding! I love the warmer months as I can start growing my summer herbs. This is because it is so handy having herbs on your kitchen windowsill. You only have to reach out for a handful of flavour to add to your cooking or salads.

Basil is delicious and will quickly fill up your windowsill with its sweet fragrance!

Growing basil from seeds indoors

Basil can be easily grown from seeds indoors during the warmer brighter days. I prefer to wait till late March to sow my seeds as spring arrives in the UK. This is also when the daylight hours have increased to help the seedlings establish well.

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You will need:

Start by getting some basil seeds. I am growing the classic variety called sweet basil here used in pesto, pasta and pizza.

Buy Sweet Basil Seeds

You will also need some fresh multipurpose compost and a clean pot or container which has holes at the bottom to allow good water drainage.

  • Fill a small pot or container with fresh multipurpose compost. Gently firm down the compost.
  • Pick up a pinch of seeds – basil seeds are tiny and sowing less is better to give them more space to germinate and grow easily.
  • Sprinkle a very light cover of compost on the seeds.
  • Use slightly tepid water to moisten the compost. You can also use a spray bottle if you have one. It is better not to be generous with the water as it may cause the seeds to rot instead.
  • Use a plastic bag to cover the pot or place in a tray that has a plastic cover – this will help to hold the temperature and humidity.
  • Leave the pot in a warm place indoors. I like to leave mine near the boiler in my kitchen.
  • After 7-14 days, you will see little green shoots peeking through the compost. Once this happens, you can take the plastic cover off and place the pot on a bright warm window.
  • Keep the compost lightly moist as I have found that basil does not like very wet compost. A great tip for you is to water from below – so place your pot in a shallow tray of tepid water for about 15 minutes only.
  • Once the seedlings have their second set of leaves (true leaves), they will be ready for transplanting into their own pots with multipurpose compost – you can plant 2-3 seedlings in each new pot.

Once transplanted, you can keep your basil plants indoors on a bright warm windowsill or move them outdoors.

Growing basil on outdoors

Once the danger of frosty nights is over, which is around May in the UK, basil seedlings can move outdoors. They will have put on a few more leaves and some height by the time the basil plants move outside!

Lots of large green leaves on small plants growing in a green rectangle tub. growing basil on a windowsill
Young basil plants ready to move outdoors!

I will be planting some of my basil with my tomatoes as they make great companions. Basil can also be planted in raised beds with other vegetables too!

Harvesting Basil

Begin picking your basil once the plants are about 15 cm in height. Ideally, pinch the tops of the basil generously so that plants can become bushier. Cut just above the point where you see two tiny leaves appearing – this is where the two new stems will soon appear.

Harvesting basil_grow-with-hema
Best way to harvest basil for a bushier plant!

Once the hot summer days start, all you have to do is keep the basil plants watered and keep picking. The more you pick, the more it will produce. If the plants go to flower, they will stop producing leaves so you might like to pinch these off when they appear. I love to harvest tubs of basil in summer for making pesto to enjoy with homegrown tomatoes!

a metal dish full to the brim with large leaves. Growing basil.
A dish full of summer basil leaves, yum!

Problems you may encounter

  • Seeds don’t germinate well

It was not warm enough for the seeds to germinate, or they were over watered. I also find that seed sowing compost does not work well for sowing basil seeds. I prefer multipurpose compost as it drains water away well and is light in texture.

  • Poor growth of seedlings

This could be because your compost is too wet. Basil does not like wet conditions. Water only to keep the compost lightly moist. Also check that that the container or pot you are using has enough holes to allow excess water to drain out.

Low light levels could be the reason too, especially if they become leggy!  Daylight is pretty dim here in the UK in the winter months. I tend to wait for late March before I start sowing basil seeds as the days become longer and brighter after that.

It could be too cool for good growth. Basil loves warmth! Give it a warm windowsill to grow on while it is young. If you are moving them outdoors, choose a sunny spot and it will not let you down!

Hope you will grow lots of basil this year, and trust me when I say this … homegrown basil is delicious and very rewarding!

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Buy your Basil Seeds

Sweet Basil Seeds

Red Basil Seeds

Greek Basil Seeds 

Posts you may also enjoy:

Growing Chives – Easy to Grow Herb

How to Grow Tomatoes – learn to grow your own!

Growing Cucumbers – how to grow from seeds

How to Make Basil Pesto

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