Veronica longifolio tall blue speedwell
The tall veronica speedwell perennial with blue spikes in my garden is similar to the Veronica longifolio ‘Blue Giant’ (Spike Speedwell) as described in Gardenia.net
Veronica longifolio Speedwell resembles the much smaller and more compact speedwell, blue Veronica Royal Candles Speedwell which is not as hardy. Veronica longifolia
It is also in the Parkdale Community Garden
These speedwells are hardy and low-maintenance and flower for a long time. They attract bees and butterflies. It flowers in July and August and can grow in sun or semi-shade.
Another Calgary garden 