Forget-me-not

Questions about forget-me-not

Does forget-me-not need sun or shade?

Forget-me-not grows in full sun (6 or more hours of direct sun a day), part sun (4 to 6 hours of sun, including some afternoon sun) and part shade (2 to 4 hours of sun, mostly in the morning).

It wants soil that stays evenly moist, of average fertility, and a good soak in dry spells. It copes with soil that stays wet.

What zones does forget-me-not grow in?

USDA zones 3 to 8. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).

Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.

Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.

When does forget-me-not flower in my zone?

In zone 5 it flowers mid April to late May. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.

Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.

How far apart should forget-me-not be planted?

8 in (20 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.

It grows 8 in (20 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.

How many forget-me-not plants do I need?

At 8 in apart, set out in staggered rows:

• 27 to fill 10 square feet (about 1 m²)
• 16 for a single row 10 ft (3 m) long
• 86 to fill a 4 × 8 ft bed on its own

In a mixed border, plant it as threes and fives, along the front and just behind it.

Is forget-me-not poisonous to dogs and cats?

No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.

"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.

What can I plant instead of forget-me-not?

Forget-me-not is listed as invasive in parts of North America, so the planner never uses it. These do the most similar job, and are native:

• Common blue violet: the same job in a bed, the same size, the same flowering time and the same colour.
• Dwarf crested iris: the same job in a bed, the same size and the same flowering time; lavender or white, not blue, wants average soil.
• Woodland stonecrop: the same job in a bed and the same flowering time; 4 in shorter, white, not blue.

Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.

Do deer eat forget-me-not?

Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.

Will forget-me-not spread?

It seeds itself about; the risk of it taking over is high. Self-seeds very freely and spreads into moist woodland and stream banks. Listed as invasive in parts of the upper Midwest, and restricted in Wisconsin. Pull the plants out before the seed ripens.

It is listed as invasive in parts of North America, and the planner never chooses it.

What flowers after forget-me-not?

Forget-me-not is over by late May. These start as it finishes and carry the same spot on, so it never goes flat:

• Creeping thyme: from early June to mid July, 3 in tall, to stand in front of it and cover its fading stems.
• Lady's mantle: from late May to early July, 18 in tall.
• Astilbe: from late June to mid July, 24 in tall.

What does forget-me-not look like in winter?

Forget-me-not holds some of its leaves into winter, more in a mild year or a sheltered spot, and they look tired by March. Cut the old ones off as new growth starts.

Is forget-me-not good for bees and butterflies?

Forget-me-not is visited by pollinators, butterflies and hummingbirds.