Fertilising guide

How to fertilise Clementine (Citrus × clementina)— schedule & NPK

Also called clementine, Algerian tangerine, seedless mandarin.

More about clementine

About Clementine

Citrus × clementina · also called clementine, Algerian tangerine · edible

A small, easy-peeling mandarin hybrid producing very sweet, juicy, usually seedless fruit in winter. Clementines are compact, often spiny trees that crop heavily and ripen early. They need plenty of warmth and sun to sweeten and are slightly less cold-hardy than satsumas, but make rewarding container citrus for conservatories and sunny patios.

Growth habit: Compact, rounded, evergreen tree, often spiny on young wood, with a dense canopy of small glossy leaves; naturally smaller than oranges, which suits pots and small gardens.

Watch for — Flower and fruit drop: Beyond natural thinning, heavy drop is caused by drought stress, irregular watering or underfeeding during fruit set. Keep moisture and nutrition steady.

What fertiliser clementine actually wants — and why

Clementine is a hungry evergreen fruiter with specific needs — a dedicated citrus feed, switched between summer and winter formulas, keeps it cropping and green.

For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for clementine: match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.

How often to feed clementine, and which months

Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For clementine:

The dormant-season rule matters more than the exact interval: skip feeding entirely when clementine is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.

What strength to mix for clementine

Follow the citrus-feed label rate for clementine and use the correct seasonal formula. The trace-element content matters as much as the NPK — substituting a general feed is the usual cause of yellowing.

Feeding always goes onto already-damp soil, never dry roots — water clementine first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the clementine watering schedule.

Signs you are over-feeding clementine

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for clementine:

Salt crust on the soil and scorched, browning leaf tips.
Excess soft leafy growth with poor fruit set from too much nitrogen.
Leaf drop shortly after an over-strong feed.

Signs you are under-feeding clementine

Yellowing leaves — overall pale, or yellow between green veins (magnesium/iron).
Poor flowering and fruit set, small or dropping fruit.
Weak new growth and a generally tired tree.

If the symptoms point at watering, light or roots rather than nutrition, the full clementine care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

Potted clementine accumulates salts and benefits from a thorough plain-water flush every couple of months until it drains freely, plus an annual repot or top-dressing of fresh citrus compost.

Organic vs synthetic feeds for clementine

Organic options

Well-rotted manure or compost mulch plus seaweed and an Epsom-salts (magnesium) drench supports clementine naturally. UK: organic citrus feed or seaweed + Epsom salts; US: Espoma Citrus-tone or Dr. Earth Citrus.

Synthetic / liquid feeds

A proprietary summer and winter citrus feed — UK: Westland or Vitax Citrus (summer/winter); US: Miracle-Gro or Espoma Citrus. Using the right seasonal formula is the key to keeping clementine green and cropping.

Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.

Fertilising clementine — frequently asked questions

What fertiliser does clementine need?

A specialist citrus fertiliser, which carries the higher nitrogen plus the magnesium, iron and trace elements citrus need — generic feeds quickly leave it yellow and chlorotic. Many ranges have a summer (higher-N) and a winter (lower-N) formula. Clementine is a hungry evergreen fruiter with specific needs — a dedicated citrus feed, switched between summer and winter formulas, keeps it cropping and green.

How often should I feed clementine?

Feed every 1-2 weeks in spring and summer with a high-nitrogen citrus fertiliser containing iron, magnesium and trace elements, then a reduced winter citrus feed in the cold months. Address interveinal yellowing with chelated micronutrients as it appears. Feed every 1-2 weeks in spring and summer with a high-nitrogen citrus fertiliser containing iron, magnesium and trace elements, then a reduced winter citrus feed in the cold months. Address interveinal yellowing with chelated micronutrients as it appears. In practice: a summer citrus feed regularly (often roughly fortnightly) from spring to autumn, switching to a winter citrus feed at a reduced rate over the colder months — citrus feed year-round, unlike most container plants.

What strength of feed for clementine?

What does over-feeding clementine look like?

Salt crust on the soil and scorched, browning leaf tips. Excess soft leafy growth with poor fruit set from too much nitrogen. Leaf drop shortly after an over-strong feed. Feeding clementine an ordinary plant food instead of a citrus-specific one is the defining mistake — it lacks the magnesium and iron citrus demand, and the leaves yellow between the veins no matter how often you feed.

Should I flush the soil of clementine?