Stop Blind Buds: Late March Rose Fertilizing Rules

The weather this year has been particularly “crazy”, with temperatures soaring above 30°C and then plummeting into the single digits. This roller-coaster of temperature changes has left plants at a loss, and roses in varying states of growth. Fertilizers should be applied with extreme caution at this time, as the wrong fertilizer may result in a large number of blind buds and non-flowering roses.

End of March to early April: Fertilizer for roses needs to be tailored to the “plant”.

Except for the cold regions in the north, roses in most areas have entered a vigorous growth period, with new buds sprouting rapidly. At this time, fertilizer needs to be adjusted according to the state of the plant, the wrong fertilizer not only can not promote flowering, and may even lead to a reduction in the amount of flowers.

1. Roses with buds on new branches

There are many varieties of roses, and the flowering period varies greatly. Some early-flowering varieties can already see small buds on the new branches, at this time, we should switch to high-phosphorus and potassium fertilizers (such as potassium dihydrogen phosphate), to avoid excessive nitrogen fertilizers that lead to the prolongation of branches, buds stunted or deflowering.

Suggested fertilization program:

Root irrigation: apply flower-promoting fertilizer or potassium dihydrogen phosphate (500 times dilution) every 5 days.

Foliar sprays (for varieties prone to drooping heads, such as ‘True Zeus’ ‘Autumn Rouge’): every 3 days (again 500x dilution).

Adequate phosphorus and potassium fertilizer can:

✅ Promote a strong root system and enhance nutrient absorption.
✅ Increase the number of flower buds, so that a single branch breeds a dozen of flower buds, forming a hand-cupped flower effect.
✅ Strengthen the branch hardness, reduce the drooping head phenomenon, so that the flowers stand up and bloom.

2. Roses with short new shoots and no blooms

New branches of late-flowering varieties may still be in bud, or have dense foliage but short branches. At this time, a balanced growth fertilizer (balanced nitrogen, phosphorus and potassium) should be used, and 1-2 additional high nitrogen fertilizers can be added to promote new branch growth if necessary.

⚠️ Caution:

Avoid using high phosphorus and potassium fertilizer too early, or it may lead to:

Insufficient nitrogen fertilizer, stagnant new branch growth.

Excessive phosphorus and potassium will prevent calcium absorption and cause terminal buds to wither (directly affecting flowering).

Branches with withered terminal buds need to be pruned to promote new growth, otherwise they will not be able to flower.

Management Tip:

To facilitate fertilizer application, it is recommended to place roses with existing buds and those without buds separately to avoid using the wrong fertilizer.