Top 8 Flowers from Seed

by Mark Cullen

Standing in front of an extensive rack of seeds at the hardware store, I reached for the cosmos. Cosmos is different from ‘The cosmos’ you may be thinking of. While you may reach for the stars, I will be very happy just reaching for a packet of seeds that will provide me with a riot of colour in my garden this summer. Like cosmos.

Not everyone who plants gardens understands that there are some enormously productive flowering plants that are best grown from seed sown directly into your garden soil. Cosmos is just one of them. It grows to about 1.2 meters and blooms its head off in a sunny garden.

Here are my top 8 picks for flowers that perform best from seed. Now is a great time of year to buy yours. I find that if I wait until spring many of my favourite varieties are not available:

  1. Nicotine. An unfortunate name for a wonderful flowering plant. While images of a hacking cough might be on your mind when you see the word ‘nicotine’, the truth is you will be blown away by the fragrance, once it is established. Come mid-summer, the nicotine in my garden is the biggest hit, late in the day when the air is still and the hummingbirds are at their peak of activity. ‘Old fashioned’ nicotine produces large clusters of trumpet shaped flowers. Grows up to 2 meters high. Loves the sun.
  2. Centaurea. ‘Cornflower’ Grows to about 80 cm high so is best at the back of the flower bed. Blue is the signature colour but others, like yellow, red and orange are also available. Cornflower is perhaps the best plant for drying to bring indoors. Come winter next year, you will glad that you grew (and picked) some Centaurea.
  1. Nigella. We don’t grow nigella to knock our eyes out with colour. We grow it to lighten up the show. Fact is, you will want to stop and pick it while you tour your garden at the end of each day this summer. Loves the sun. Features light, airy foliage. It is the ‘rice crispies’ of the garden. Often called ‘wild fennel’.
  2. Calendula. ‘Pot Marigold’. I am not sure how this low-growing flowering plant got the name ‘pot marigold’. It is neither a marigold nor would anyone in their right mind smoke it. All I know for sure is that this plant produces masses of yellow or orange flowers mid summer. I sow them in a row in my veggie garden and pick them to bring indoors. They stand up quite well in a vase and honey bees frequent the blooms in your garden. An edible flower. Thrives in full sun. Grows to 30 cm high.
  3. Zinnia. Create a riot in your garden. If I could only recommend one flowering annual plant to you, it would be zinnias. Providing you have lots of sun. Zinnias are very reliable germinators. You can cut them and bring them indoors where they can last for up to 10 days. There are many varieties available, ranging in heights from the 30 cm Pom Pom to giant, well, ‘Giant’ zinnias that mature at about a meter high. They are available in a riot of colours. Require a location in full sun.
  4. Sunflowers. I grow about 12 varieties of sunflowers. But then, I have a big garden. Sunflowers can take up a lot of space but man, are they easy to grow! Get kids in on the action starting on the day of sowing the seeds. They will love the speed with which they explode through the soil and the growth that can occur during one hot, sunny day. If you have an average or small garden, consider some of the popular varieties that only mature to about 50 cm or less: Teddy Bear, Junior and Dwarf Pacino.
  5. Nasturtium. Low growing, sometimes with a vine-like growth habit. ‘Hot colours’ that produce for several weeks in the garden. They love the sun but last best in a ‘cool’ part of the garden facing east. When they look their best they are stunning. My favourite variety is Whirly Bird as they bloom outside of the foliage (while some varieties hide their flowers). Grows to 40 cm.
  6. Morning Glory. If you didn’t grow morning glories as a kid, you really missed out. But then, you can do it now and BE a kid all over again. A twining vine that needs vertical support at least 2 metres high. They produce large quantities of medium sized, trumpet shaped blue flowers that are very attractive to hummingbirds. But here is the catch: they perform best in marginal soil. If you are adding to your garden soil when sowing the seed, be sure to mix in about 30 to 40% clay. When you make growth a little tough for a Morning Glory you encourage it to bloom like crazy. Don’t fertilize.

Mark Cullen is an expert gardener, member of the Order of Canada, author and broadcaster. Get his free monthly newsletter at Look for his new best seller, ‘The New Canadian Garden’ published by Dundurn Press. Follow him on Twitter @MarkCullen4 and Facebook.