Backyard Grapes Identify & treat grapevine problems
Disorder moderate severity

Iron deficiency

Lime-induced chlorosis

Yellowing of the youngest tip leaves with green veins — usually a high-pH soil problem, not a lack of iron.

Lime-induced chlorosis: pale yellow young leaves with green veins at a shoot tip Photo: Karl Bauer Wikimedia Commons CC BY 3.0 AT
Iron deficiency in grapevine: pale yellow interveinal chlorosis on young leaves while the main veins stay green Yara UK
Iron deficiency: grape leaves turn completely yellow PowerAG

Description

Iron deficiency, often called lime-induced chlorosis, is the mirror image of magnesium deficiency: it strikes the youngest leaves at the shoot tips rather than the old ones, because iron doesn’t move around inside the plant to be recycled into new growth. Those tip leaves go yellow between fine green veins, and in bad cases turn almost white and scorch at the edges.

The crucial point is that it’s rarely about how much iron is in the soil — it’s about availability. On alkaline, high-lime soils (and in cold, wet, or waterlogged conditions) iron gets locked into forms the vine can’t take up, so simply adding ordinary iron does little. A chelated iron formulated for high pH (Fe-EDDHA) gives quick relief, but the real fix is managing drainage and soil pH so the iron already present becomes available.

What to look for

  • Interveinal yellowing of the youngest leaves at the shoot tips; the fine veins stay green.
  • In severe cases new leaves turn cream to almost white and the margins scorch.
  • Older, lower leaves stay green — the reverse of magnesium deficiency.
  • Weak shoot tips and reduced growth when it is severe and prolonged.

Treatment options

Cultural & prevention

Start here — habits that stop problems before they spread.

  • Improve drainage and avoid waterlogging, which is a frequent trigger on heavy soils.
  • Don't over-lime; test and avoid pushing soil pH higher.
  • Build organic matter, which slowly improves iron availability.

Organic / low-toxicity

Gentler sprays and biologicals for active outbreaks.

  • Chelated iron (choose Fe-EDDHA for high-pH soils) as a soil drench or foliar spray for a quick fix.
  • Long term, manage soil pH rather than repeatedly dosing iron.

Sources

This entry is based on the references below. Read them for full detail and for spray timings and rates valid where you live.

  1. Grape (Vitis spp.)-Iron Chlorosis — Pacific Northwest Pest Management Handbooks (OSU / WSU / Univ. of Idaho)
  2. Viti-notes: Grapevine Nutrition - Trace Elements — Australian Wine Research Institute (AWRI)
  3. Monitoring Vineyard Nutrition — Oregon State University Extension