Vitamin C serum is one of the simplest steps you can add to a skincare routine, but a few small habits help you get the most from it. Here is how to use it, without overcomplicating things.
Morning or evening?
Both work, and the honest answer is that the one you actually stick to wins. Vitamin C is an antioxidant, so there is a sensible logic to applying it in the morning: it goes on before the day’s environmental exposure, and it sits neatly under moisturiser and sunscreen. Plenty of people prefer it at night instead, when their routine is less rushed.
The Kessine label directs 2-3 drops on clean skin morning and evening. If twice a day does not fit your life, once a day is completely reasonable. Consistency matters more than frequency, and a serum used every morning will do more for you than one used twice a day for a fortnight and then abandoned.
Where it goes in your routine
A serum goes on after cleansing and before moisturiser. The simple sequence is cleanse, then serum, then moisturiser, then sunscreen in the morning.
The general rule for layering is thinnest to thickest. A lightweight, water-based serum needs to reach clean skin, so it goes on early rather than sitting on top of a heavier cream. If you use a toner or an essence, that goes between cleansing and serum. Sunscreen is always last in the morning, over everything else.
How much to use
Two to three drops is enough for the whole face. More is not better with a serum. A larger amount is not absorbed any better, it simply runs out faster. Press it gently into clean skin across the face and neck rather than rubbing it in hard.
Layering it with other products
Vitamin C sits comfortably alongside most of what people already use. Hyaluronic acid is a common pairing and layers well: serum first on clean skin, then hyaluronic acid, then moisturiser. Kessine already contains Sodium Hyaluronate, the salt form of hyaluronic acid, so you may find a separate one is unnecessary.
Niacinamide is also fine to use in the same routine, despite a persistent internet rumour to the contrary. If you use a retinoid, most people prefer to keep vitamin C to the morning and the retinoid to the evening, simply because that is gentler on the skin than stacking two actives at once.
Give it time
Skincare rewards consistency over intensity. Used daily, a vitamin C serum helps skin look fresher and brighter over time. Think in weeks rather than days. If you want to judge it fairly, take a photograph in the same light when you start and compare a few weeks later, rather than examining the mirror each morning.
Storage, and why some serums change colour
Vitamin C can be sensitive to air and light, which is why many serums turn yellow or brown on the shelf. That colour change is oxidation, and it is most common with pure L-Ascorbic Acid.
Kessine is formulated with Sodium Ascorbyl Phosphate, a stable derivative of vitamin C that does not oxidise the same way, so it stays clear and pale for longer. Keeping the bottle closed and out of direct sunlight is still good practice. The bottle carries a batch number and expiry, and it is best used within 6 months of opening.
The simple version
Cleanse. Two to three drops of serum on clean skin. Moisturiser. Sunscreen in the morning. That is the entire routine, and it takes less than a minute.
Kessine Kakadu Plum Vitamin C Serum is fragrance-free, made in Australia, and designed to slot into exactly this kind of simple daily ritual. Patch test before first use.
Common questions
Should I use vitamin C serum in the morning or at night?
Both work. Vitamin C is an antioxidant, so mornings are a natural fit under moisturiser and sunscreen, and many people prefer it then. The Kessine label directs 2-3 drops morning and evening. If twice a day does not suit you, once a day used consistently is far better than twice a day used occasionally.
Can I use vitamin C serum every day?
Yes. Vitamin C serum is designed for daily use, and consistency matters more than intensity. Kessine uses Sodium Ascorbyl Phosphate, a gentler and more stable form of vitamin C than pure L-Ascorbic Acid, which is one reason it suits a daily routine. If your skin is reactive, start once a day and build up.
What order do I apply vitamin C serum in?
Cleanse, then serum, then moisturiser, then sunscreen in the morning. The general rule is thinnest to thickest, and a water-based serum goes on early so it is not sitting on top of a heavier cream. If you use a toner, it goes between cleansing and serum.
Can I use vitamin C serum and hyaluronic acid together?
Yes, and they layer well. Apply the vitamin C serum to clean skin first, then hyaluronic acid, then your moisturiser. Kessine already contains Sodium Hyaluronate, the salt form of hyaluronic acid, so you may find you do not need a separate one.
How many drops of vitamin C serum should I use?
Two to three drops is enough for the whole face. More is not better with a serum. A larger amount is not absorbed any better, it simply runs out faster.
How long does it take to see a difference?
Skincare rewards consistency, and most people think in terms of weeks rather than days. Used daily, a vitamin C serum helps skin look fresher and brighter over time. Photographs in the same light a few weeks apart are more reliable than checking the mirror each morning.
Does vitamin C serum expire, and how should I store it?
Yes. Kessine carries a batch number and expiry on the bottle and is best used within 6 months of opening. Vitamin C can be sensitive to air and light, which is why some serums turn yellow or brown over time. Sodium Ascorbyl Phosphate is more stable than L-Ascorbic Acid, so it holds up better, but keeping the bottle closed and out of direct sunlight is still good practice.