Tall Annuals

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berkemeier / Pixabay

There isn’t always room in a garden to add more perennials, but something tall may be desired. What can you plant from seed or buy from the nursery that will add height for a single season?

Sweet peas have been in our prairie gardens for generations. They come in many heights, colours, scents, blossom size, etc. so reading the seed package is a must. Sun-loving, and thirsty, they will reach up to 6 ft. in the right location. This plant will bloom and bloom for weeks as long as you cut the blossoms and take them in the house where they are most satisfying on the kitchen table. As soon as you allow them to set seed pods (they are, after all, peas) their job is done, and that is the end of the flowers. The seed can be planted directly into the garden in the spring, but you will get blooms earlier if you start them inside in April and transplant in May, especially if Mother Nature decides to give us a cool wet spring and they find themselves with cold feet. They need something to climb on; netting is best. A tall teepee made of bamboo poles tied together at the top and wrapped with pea netting can be very pretty when covered with sweet peas. If your garden includes small children, leave an opening for them to crawl inside.

A similar trellis also works for climbing beans, the most dramatic being Scarlett Runner Beans. They like our summers so much you need really tall poles (one year in my garden they stretched from the top of their poles and into the overhanging crab-apple tree and must have reached 12 ft. before frost put an end to their adventure). Some years you get tasty beans, and some years you will have to be satisfied with the brilliant red blossoms. Other beans also climb; one of my favourites is the Italian Purple Bean, which always produces masses of long tasty beans (sadly, they turn green when cooked, but are worthwhile, nonetheless).

Everyone who gardens in pots knows the Sweet Potato Vine, with its lime green or deep purple leaves. It doesn’t just cascade onto the patio stones, you know. If you give it a trellis to climb and spend a few minutes now and then to secure it, this is another one that will give interesting and beautiful height to a patio or deck. Furthermore, it tolerates shade very nicely as well as poor soil.

Ipomoea purpurea or tricolor, Morning Glory Vine, on the other hand, expects to be fed regularly if she is to provide you with a profusion of bright blooms, a new one each day. These will provide pleasure for weeks in the right sunny location.

When I was in Costa Rica, I was blown over by the lush hedges and arbours covered entirely with Thungergia alata, Black-Eyed Susan Vine. The exact same plant here will climb or trail, depending upon what support you provide, and gives a pretty display from a pot on the deck. This one also is happy in a part shade location. Annual here; perennial in Costa Rica.

Last of all, we can’t ignore the stately Sunflowers and Hollyhocks. The giant varieties grow very tall indeed and make a dramatic statement at the back of the garden or along a fence. From mid to late summer, these guys get taller and stronger, the sunflower also providing seeds for birds and squirrels. My hollyhocks still had bright red blooms at the tip top of their stalks when our first snow fell last fall. Hollyhocks are biennial not annual, and bloom during their second year of life, so you need to start them off two years in a row. They self-seed readily and will look after that flower bed by themselves after that.