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Getting it to bloom

Why won't my Acer rubrum 'Autumn Blaze' bloom? (and how to make it flower)

Also called Autumn Blaze Maple (Acer rubrum 'Autumn Blaze').

More about acer rubrum 'autumn blaze'

About Acer rubrum 'Autumn Blaze'

Acer rubrum 'Autumn Blaze' · also called Autumn Blaze Maple · flowering

'Autumn Blaze' is a vigorous freeman maple hybrid (Acer rubrum × saccharinum) combining red maple's long-lasting orange-red autumn colour with silver maple's fast growth and adaptability. It forms a broadly oval, well-branched shade tree, carries small red spring flowers, and tolerates a wide range of soils and urban conditions in full sun.

Plant type: flowering

The reasons acer rubrum 'autumn blaze' isn't blooming

Almost every non-blooming acer rubrum 'autumn blaze' traces back to one of these, roughly in order of how common they are:

  1. Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.
  2. Too much nitrogen feed, driving lush foliage at the expense of flowers (very common with general or lawn feeds).
  3. The plant has not been deadheaded, so it stops flowering once it sets seed.
  4. Irregular watering — drought or waterlogging at the budding stage makes buds abort.
  5. It is still too young or was checked by a transplant and is rebuilding before flowering.

Feeding acer rubrum 'autumn blaze' a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

The fix — how to get acer rubrum 'autumn blaze' to flower

  1. Maximise sun. Give acer rubrum 'autumn blaze' the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers.
  2. Switch the feed. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.
  3. Deadhead regularly. Remove spent flowers often to keep it producing more rather than stopping to set seed.
  4. Water consistently. Keep moisture even through budding and flowering — drought-then-flood swings make buds drop.

Light and feeding do most of the heavy lifting here. Dial in the spot with the light guide for acer rubrum 'autumn blaze' and get the feeding right with the acer rubrum 'autumn blaze' fertilising schedule — the wrong feed (too much nitrogen) is one of the most common silent reasons a healthy plant makes leaves instead of flowers.

Bloom season and what to expect

Acer rubrum 'Autumn Blaze' flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

Post-bloom care so it flowers again

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

For everything else this plant needs day to day, see the full acer rubrum 'autumn blaze' care brief and its watering schedule — a stressed, badly watered plant rarely has the energy to flower at all.

Acer rubrum 'Autumn Blaze' blooming — frequently asked questions

Why won't my acer rubrum 'autumn blaze' flower?

Acer rubrum 'Autumn Blaze' blooms on the season's growth given enough sun, warmth and the right feed — there is no cold or photoperiod trick, just good growing conditions and a bloom-leaning feed. The most common reason it is not happening: Too little sun — most of these need full sun (or very bright light) to flower well; shade gives leaves, not blooms.

How do I make acer rubrum 'autumn blaze' bloom?

Give acer rubrum 'autumn blaze' the sunniest spot you have — for most bedding and fruiting plants, more direct light directly means more flowers. Move off high-nitrogen feeds and use a higher-potassium "bloom" or tomato-type feed as it comes into flower.

When does acer rubrum 'autumn blaze' normally bloom?

Acer rubrum 'Autumn Blaze' flowers across its growing season (mostly summer) and, kept fed and deadheaded, can bloom for many weeks or right up to frost.

What should I do with acer rubrum 'autumn blaze' after it flowers?

Deadhead, keep feeding lightly, and many will rebloom; collect seed from the best plants at the end of the season if you want to grow them again.

What is the single biggest mistake stopping acer rubrum 'autumn blaze' flowering?

Feeding acer rubrum 'autumn blaze' a high-nitrogen general feed and growing it in too little sun — you get a big leafy plant and almost no flowers.

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