Blueberry

What it needs, briefly

Light

More than six hours of sun; afternoon shade helps where summers are hot.

Water

Consistently moist, never waterlogged. The roots are shallow, so it feels drought quickly, and it rots in standing water.

Soil

Acidic (pH 4.5-5.5), rich in organic matter, free-draining. In a pot, a bark-heavy mix.

If you can see this

• Nutrient deficiency

  New leaves yellow with the veins staying green

  Likely cause

  Iron is not being taken up. Almost always because soil pH is too high: the iron is there, but the plant cannot dissolve and absorb it at that pH.

  Don't confuse it with

  The most important distinction on this page. Feeding iron removes the symptom for a while and leaves the cause; the lasting fix is lowering the pH. Farmagile files the two under different branches: one a deficiency, the other a growing condition.

• Growing conditions

  The plant sits still: small, pale leaves, no real growth for years

  Likely cause

  Soil pH too high. A blueberry in this state does not die, it simply does nothing, which is why it is usually noticed late.

• Growing conditions

  Leaf edges browned and dry, shortly after feeding

  Likely cause

  Fertiliser burn. Blueberries are more salt-sensitive than most fruit; an application that is fine on another plant can scorch these roots.

• Disease

  Fruit covered in a grey, fuzzy mould

  Likely cause

  Grey mould. It appears in damp weather and on congested, poorly aired plants.

• Disease

  The plant wilts in midsummer even though the soil is moist; roots are brown

  Likely cause

  Root rot. Blueberries do not tolerate standing water; in heavy soil this is the most common way they die.

  Don't confuse it with

  Reading the wilt as thirst and watering more is the single most common way this gets worse.

The difference is in the second look

Answering one photo is the easy part. With Blueberry, whether the advice worked only shows days later, which is why Farmagile comes back and asks.

1. 1Today: upload the photo, get the finding and what to do about it.
2. 2A few days later the app comes back and asks: did it get better?
3. 3If it didn't: a second look from a new photo, free, this time knowing what the first one said. If it is still unclear, there is an agronomist behind it.

Nothing you do about pH shows within a week. Acidify the soil and the leaves that already yellowed will not turn green again; the measure is the colour of the new leaves three or four weeks later. An approach that answers one photo and never comes back to ask is most misleading on exactly this plant.

Seeing this on your own plant?

No account needed. You see the answer first.

Other plants

• Strawberry
• Tomato