N Deficiency

Nitrogen (N) deficiency occurs when the rose is not supplied with enough nitrogen — typically because the soil is poor, fertilisation is insufficient, or the soil is too alkaline to make N available. Nitrogen is the main building block of chlorophyll, so a shortage produces uniform yellowing that begins on the older (lower) leaves and progresses upward, with overall slow, stunted growth. Because N is a mobile nutrient, the plant withdraws it from older leaves to feed new growth.

The principle for correcting N deficiency is: rapid rescue via foliar feeding + durable recovery via root-zone feeding.

• Step 1 (rescue): Apply a nitrogen-containing foliar spray (urea at 0.3–0.5%) or a high-nitrogen foliar fertiliser directly to the leaves. Uptake is much faster than waiting for root absorption.
• Step 2 (recovery): Drench the root zone with a soluble NPK supplement, organic nitrogen, or a slow-release nitrogen fertiliser to maintain steady growth.
• Note: Never overdose nitrogen during the midday heat — it can scorch the leaves. Always apply in the early morning or late afternoon.

Recommended products

Below are three widely available and effective options:

1. Dau Trau 501 (N-P-K 30-15-10) — for shoot and leaf flushes

• Description: A classic foliar fertiliser; the high nitrogen content (30%) greens up the foliage quickly and pushes strong new shoots.
• Dosage: 1–2 g per 1 L of water.
• Application: Spray evenly over the foliage or drench around the base.
• Frequency: Every 7–10 days until the canopy returns to a healthy green.
• Where to buy: Shopee — Dau Trau 501

2. Bio Fish (organic fish-emulsion nitrogen)

• Description: Fish emulsion is an excellent organic nitrogen source for roses — rich in amino acids that not only green the foliage but also thicken the leaves and improve disease resistance.
• Dosage: 10 ml per 2 L of water.
• Application: Water into the root zone or apply as a foliar spray (note: fish emulsion has a distinctive smell).
• Frequency: Every 10–15 days.
• Where to buy: Lazada — Bio Fish fish-emulsion fertiliser

3. Map Duy 30-10-10 ultra-fast germination foliar fertiliser

• Description: Fully soluble foliar feed for severely nutrient-starved roses struggling to break new growth.
• Dosage: 20 g per 16–20 L tank (about 1 g per litre).
• Application: Spray directly over the whole canopy.
• Frequency: Every 7 days during the treatment phase.
• Where to buy: Tiki — 30-10-10 foliar fertiliser

Expert tip: If the leaves are yellow but the veins remain green, the issue is more likely a micronutrient deficiency (iron or magnesium), not nitrogen. Always check the chlorosis pattern carefully before fertilising for best results.

• Establish a regular nitrogen fertilisation schedule.
• Test the soil before planting.