There are very few perennials (plants that come back every year) that bloom long term, but if you select plants based on when they bloom, you can have color all season.
Buying Plants at Summer’s End
The best time to buy perennial plants is in late summer into fall when they go on sale. Just because a plant looks dreadful, doesn’t mean it won’t thrive and grow given the right circumstances. You can plan your new perennial garden and fill it in now so the plants will have a head start come next spring. Next year, you can fill in any plants not available now. Just pay attention to what the tag says the mature size will be and give them room. Remember, that most perennials need at least three years before they reach full maturity. Plant perennial milkweed if you are an advocate of preserving the endangered Monarch Butterfly. Milkweed is one of a few plants they will lay eggs on.
One of the earliest plants to bloom is Lenten Rose (Helleborus orientalis), as it blooms right around the time of Lent in late winter or early spring and frequently shines right through the snow. Next, look for Daffodils to start blooming around mid-March as the weather warms up. Daffodils are bulbs and must be planted in the fall. After the daffodils, come perennial tulips (Tulipa – also bulbs), but squirrels and moles like to eat them so protect them from critters.
Perennial Bloom Times
Below is a sampling of other perennials and their bloom times which may be earlier or later than those identified here depending on weather patterns each year.
- March to April – Virginia Bluebells (mertensia virginica)
- April to May – Bugleweed (Ajuga reptans); Columbine (Aquilegia); Bleeding Heart (Lamprocapnos spectabilis); Wild Geranium (geranium maculatum)
- May to June – Astilbe (Astilbe); Threadleaf Coreopsis (Coreopsis verticillate ‘Zagreb’);
- June – Lady’s Mantle (Alchemilla mollis);
- June to August – Bear’s Breeches (Acanthus spinosus); Hollyhock (Alcea rosea); Butterfly Weed (Asclepias tuberosa); Purple Coneflower (Echinacea purpurea);
- June to September – Yarrow (Achillea)
- June to Frost – Black Eyed Susan (Rudbeckia – has several varieties)
- July to August – Shasta Daisy (leucanthemum x superbum);
- July to September – Plumbago (Ceratostigma plumbaginoides); Garden Phlox (Phlox paniculate);
- July to October – Hardy Begonia (Begonia grandis)
- August to September – Japanese Anemone (Anemone hupehensis); New England Aster (Symphyotrichum novae-angliae); Joe Pye Weed (Eutrochium purpureum); Cardinal Flower (Lobelia cardinalis)
- September to October – Stonecrop (Hylotelephium – includes Autumn Joy); Rough Goldenrod (Solidago rugosa);