Time is quickly ticking down to the point where we will all soon be moving from the garden-planning stage to the more fun working-in-the-garden stage. With that in mind I’m just going to quickly run through a few more suggestions that you might consider for your annual flower beds. In the past few Garden Gossip columns we’ve looked at some very common annuals and today I’d like to introduce a couple lesser used, but equally fun, annual ornamentals.
One of my absolute favourite annual flowers is also one of the easiest you will ever grow. Cosmos is a summer to fall flowering annual that is adorned with lacy green foliage and strikingly vibrant blooms in a wide array of colours. Some plants, in prime growing conditions, will push the one meter mark in height while remaining remarkably slim and well mannered. Each plant can be covered in a profusion of daisy-like blooms that are long lasting and make marvelous cut flowers. Thriving in full sun and rich soil, cosmos can also survive a fair bit of neglect while continuing to put on a show. You can start cosmos seeds indoors as little as four or five weeks before the last frost date but it is actually just as easy to direct sow the seed onto freshly disturbed soil right before a rainfall. These direct sown plants will not be far behind anything that you transplant into the garden. Take care to dead head your cosmos and they will bloom until frost. Leaving a few later flowers on each plant to mature will ensure that seeds will be available for next year. You can simply collect the large cylindrical seeds and save them in a cool dry place until you’re ready to plant them the following season. Some seeds will self sow.
Very similar to cosmos in care and growth are the strawflowers. The main difference here is that strawflowers do benefit from an early indoor start as they take just a little longer to get themselves up and growing. Sprinkle the fine seeds on top of a damp lightweight seed starting mix and spray with a mister. Place the seed tray in a bright (the seeds need light to germinate) warm area and cover with a humidity dome or plastic wrap. Once the seedlings germinate they will quickly grow to a size where they can be separated into individual growing cells. Harden them off and transplant out once the soil has warmed up to where you would ordinarily be planting out petunias, marigolds and zinnias (all great warm weather annuals). Strawflowers should be watered in at planting and once their roots establish, they can withstand plenty of neglect. Just don’t let them dry out completely. If you do water your strawflowers, avoid soaking the foliage as they are very susceptible to mildew issues. When your strawflowers bloom, do NOT dead head them. Once the majority of blooms on a stem are open, cut the entire stem so that you have about a fifteen to twenty centimeter stalk to work with. Hang these stalks upside down in a warm shaded area and they will quickly dry while retaining their vibrant colours. Properly dried strawflowers can be the mainstay of dried flower arrangements for years without losing any of their pizazz.
And what about growing annuals for colourful foliage instead of their flowers? If this interests you, and why wouldn’t it, coleus is the perfect place to start. Coleus is a family of shade loving plants that are grown for their crazily colourful foliage. These plants can have variegated leaves in just about every colour imaginable. One really neat thing about coleus is that despite being an annual, they can also be a one time purchase. Your first plants can be purchased as bedding plants or grown from seed. Then, every fall before the killing frosts, take cuttings from your favourite coleus plants and place them in a glass of water on a not-too-bright windowsill. They will quickly root and can be potted up and kept over winter as very attractive houseplants. Watch these cuttings closely for the first couple of weeks to ensure that you aren’t also overwintering aphids. The following spring, once the danger of frost has passed, plant them right back outdoors again. In this manner a single coleus plant can be repeatedly cloned and kept going for years. Coleus will exhibit their best colours in shaded areas with moist rich soils. When they do flower, you can simply remove the flower stalks as soon as you see them. The tiny coleus flowers are seldom worth leaving on the plant as they divert energy from the attractive leaves.
If you plan to grow coleus from seed simply press the tiny seed into the surface of damp seed starting mix and gently mist. The seedlings will start tiny but grow quickly.
There are thousands of other possible annuals to consider for our northern gardens. We will visit a few more of them in greater detail as the garden season goes on. For now, enjoy the spring weather!
