Vitalink Buddy - PK Booster for Bigger, Better Flowers
Best for: Growers wanting a straightforward PK boost through flowering without overcomplicating their existing feed.
Our thoughts
Buddy is one of the more established PK boosters around for a reason - it's a low-concentration formula you can run for weeks rather than a short, sharp spike that's easy to overdo. Straightforward nutrients that work consistently without complications. One we sell a lot of because it just does what it says.
Vitalink Buddy is a PK (phosphorus and potassium) booster designed to be added alongside your main nutrient line through the flowering stage, encouraging heavier flower and fruit development and improving overall produce quality. It carries a potassium-to-phosphorus ratio of roughly 3.5:6, with added magnesium and sulphur included specifically to support the plant's uptake and use of that extra P and K, since both minerals play a role in photosynthesis and nutrient transport.
Because Buddy is a relatively low-concentration PK solution, it's designed to be run over a longer window rather than a short, intense boost - typically from around week 3 of flowering through to week 8. That makes it more forgiving to dose than some high-strength boosters, where a small measuring error can tip plants into nutrient burn.
How it compares
PK boosters are one of the most crowded categories in the nutrient aisle, with Canna's PK 13/14 and Terra Aquatica's Bud/Ripen boosters as established alternatives.
- Lower concentration than Canna PK 13/14, which is designed for a short, sharp late-flower boost rather than sustained use across most of flowering
- Comparable role to Terra Aquatica (formerly GHE) Ripen, though dosing windows and concentration differ between the two ranges
- Added magnesium and sulphur alongside the core PK is a specific formulation choice not every competitor booster includes as standard
The trade-off is dosing more often over a longer period rather than a short, high-strength addition, which suits growers who prefer a steadier, lower-risk approach.
Usage guidance
Getting the dose and timing right through flowering is what makes a PK booster worth using.
Starting dose
Add at around 0.5ml per litre alongside your main nutrients from roughly week 3 of flowering.
Increasing through flower
Gradually increase to around 1ml per litre as flowering progresses, tapering off as you approach harvest and move into a flush period.
Mixing order
Add Buddy to your reservoir alongside your base nutrients rather than on its own, and check pH after mixing since PK boosters can shift solution pH.
Monitoring
Watch leaf tips for signs of nutrient burn if you're running Buddy alongside other boosters - stack multiple additives cautiously rather than at full dose each.
Technical specifications
- Type: PK (phosphorus/potassium) flowering booster
- K:P ratio: approx. 3.5:6
- Added elements: magnesium, sulphur
- Dosage: 0.5-1ml per litre
- Usage window: approx. week 3 to week 8 of flowering
- Sizes available: 250ml, 1 litre, 5 litre
- Compatible media: soil, coco, hydroponics
Who this is for
- Growers wanting a sustained PK boost rather than a short late-flower spike
- Anyone running a base nutrient line that needs a straightforward flowering additive
- New growers who want a lower-risk, more forgiving dosing window
- Growers already familiar with the Vitalink range wanting a matched booster
Best suited to flowering-stage feeding where consistent, sustained PK support matters more than a short sharp boost.
Our take
Buddy earns its popularity by being genuinely easy to use well - the lower concentration and longer usage window mean less risk of getting the dose wrong compared to sharper, short-window boosters. It represents solid value-for-money for what it does.
Does exactly what it should, day in, day out, through most of your flowering cycle.
