Ornamental Grasses and Shrubs – Full Sun Hot Yard

(Question)

Oakville – backyard – 10-12 hours a day full sun – blazing hot in the summer

What (if any) ornamental grasses, shrubs, flowers that are perennials do well in low grade (clay escarpment) soil and full sun all day long?

(Answer)

Clay soil is a much discussed topic on the Master Gardener Website. (See references below). In order to be successful in growing anything in your garden, regardless of the sun, you really need to amend the soil first by adding some organic matter (compost) or a good triple mix.

“Working with clay soil requires much patience. The problem with clay is that the particles (aggregates) are small and fit together fairly tightly leaving very little space between for drainage or oxygen. Because of the lack of oxygen and drainage the plants have difficulty absorbing nutrients and attaining the amount of oxygen they need to function properly… The best supplements for clay increase organic content. Compost, Leaf mulch (mowed leaves in the fall) and store bought mulch laid on top of the soil will slowly work its way down and start loosening up the clay. As you increase organic matter the worms will follow and oxygen and nutrients should over time become more available to plant roots. ” Amending Clay Soil. Toronto Master Gardener Post, Aug. 27, 2015

Creating flower beds from scratch in clay soil

How to Fix Clay Soil

When it comes to what to plant in your garden the list is endless.  Plants native to Southern Ontario would be a good place to start.  Click here  for further suggestions.  Here are some names of other perennials for hot dry soils.  Of course your choices will be limited to what you can find in your local garden centre or nursery.  Furthermore, the size of your garden will determine what plants would be appropriate.

Anthemis tinctoria (Golden marguerite daisy)
Asclepias tuberosa (Butterfly weed)
Echinops ritro (Globe thistle)
Euphorbia sp. (Spurge)
Gaillardia sp. (Blanket flower)
Hemerocallis hybrids (Daylily)
Physostegia virginiana (Obedient plant)
Rudbeckia sp. (Blackeyed Susan)
Sedum sp. (Stonecrop)
Stachys byzantina (Lamb’s ears)
Thymus sp. (Garden Thyme)

The following grasses do well in full sun, however most grasses do need well drained soil.  This why you really need to amend your soil before any planting takes place.  To supplement this list you may like to visit the Royal Botanical Garden (closeby) and see the grasses growing there – for ideas.

Calamagrostis x acutiflora ‘Karl Foerster’ –  Feather reed-grass

Pennisetum alopecuroides – Fountain grass

Schizachyrium scoparium – Little bluestem

Panicum virgatum – Switch grass

Helictotrichon sempervirens – Blue oat grass

Andropogon gerardii – Big blue stem                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                The following link will take you to a previous Master Gardener post that includes a list of ornamental shrubs for growing in sun.

Ornamental Shrubs for Various Light Conditions: A Toronto Master Gardeners Guide