If you’re looking to grow flowers for vibrant summer colour, look no further than zinnias. With so many zinnia varieties available, it’s no wonder they’re such a popular cut flower.
Zinnias can be sown indoors from February to April, but can also be sown outside in May. Just choose a fertile, weed-free area, whether it’s a gap in a border or a patch of bare soil, and get sowing.
Once they’re in bloom you can expect a profuse display of summer colour up until the first autumn frosts.
Learn how to sow zinnia seeds outdoors, below.
You Will Need
- Rake
- Soft string or twine
- Zinnia seeds
Step 1
Rake weed-free soil to a fine, crumbly consistency. Use a taut string to make a straight line and take out a shallow drill.

Step 2
Sow the seeds along the drill, making sure they are 10-15cm apart. Use your hand to fill the drill with soil, lightly covering the seeds.

Step 3
Water the seeds well, adding a label to the area so you know what you’re growing. Keep the soil most, but not saturated, as seedlings begin to grow, and cover with a cloche.

Step 4
When seedlings have formed a couple of pairs of leaves, thin them to around 30cm apart. Water frequently in dry weather and keep weed-free.

Zinnias for pollinators
Zinnias are attractive to pollinating insects, particularly hoverflies. To ensure they can reach the pollen and nectar, grow single-flowered varieties that don’t block pollinator access.Â
