Quick answer: CANNA call their feed chart a Grow Schedule, and there is one for each of their lines: Terra (soil), Coco, Aqua (recirculating hydro) and BioCanna (organic soil). Doses are given in millilitres per 10 litres of water. The chart runs from a short rooting phase through two vegetative phases and four generative (flowering) phases, finishing with a nutrient-free week. Each phase has an EC target, and CANNA are clear that you add the EC of your own tap water to the figure on the chart. Pick the chart for your line and substrate, and start at the low end of each range.
CANNA is one of the most asked-about ranges in our shop, partly because the chart uses phases rather than plain week numbers. Once you see how the phases map onto your crop it is very easy to follow. Here is how we explain it.
Where to find the official chart
CANNA publish the charts free on canna-uk.com under Grow Guide. There are printable PDFs for Terra, Coco and Aqua, and an online Grow Guide generator that builds a chart for your tank size, your water (soft, normal, hard or RO), how long you keep plants in veg, how many weeks you flower for, and a light, normal or heavy feeding schedule. CANNA say the normal schedule suits most circumstances. Always work from the current version; the layout has changed in recent editions and older copies still circulate online. If in doubt, bring yours in and we will check it.
Step 1: Pick the chart for your line
- Terra: for soil, with Terra Vega in growth and Terra Flores in flower. One-part feeds, no A and B.
- Coco: for coco coir, with Coco A+B as the base feed through the whole cycle. The same bottles do growth and flower; only the dose changes.
- Aqua: for recirculating hydro systems, with Aqua Vega A&B in growth and Aqua Flores A&B in flower.
- BioCanna: the organic soil line, with Bio Vega and Bio Flores. Its chart is simpler, with no EC rows.
Step 2: Understand the columns
The chart is split into phases rather than fixed weeks, and each phase lasts a range of weeks depending on your crop.
Rooting / Start
The first few days after potting on, when Rhizotonic is at its highest dose and the base feed is low.
Vegetative Phase I and II
The growing stage under 18 hours of light. Base feed steps up through the two phases. If you want a longer veg, CANNA's rule is to repeat Vegetative Phase I.
Generative Phase I to IV
Flowering, under 12 hours of light. Base feed peaks in the middle phases. Generative Phase II is the single week in which PK 13/14 is used, and CANNA place it about three to four weeks before harvest. If you flower for longer, repeat Generative Phase I. The last phase is nutrient-free: plain water, with Cannazym if you wish, so the plant uses up what is left.
Step 3: Understand the rows
Doses below are from CANNA's own charts and product pages, per 10 litres of water. Divide by ten for a 1 litre figure.
Base feeds
- Terra Vega: roughly 15 to 35ml at rooting, rising to 30 to 55ml through veg. Terra Flores: 50 to 70ml in early and mid flower, easing to 40 to 60ml late on.
- Coco A+B: 15 to 25ml of each part at rooting, rising through veg to 30 to 40ml of each in mid flower, then 20 to 30ml late on. Always equal amounts of A and B.
- Aqua Vega A&B / Aqua Flores A&B: CANNA's product pages give 20ml of each part per 10 litres for Vega and 30ml of each for Flores as the working rate; the chart adjusts that by phase.
- Bio Vega / Bio Flores: around 20ml and 40ml per 10 litres respectively on the BioCanna chart.
Roots and root zone
- Rhizotonic: 40ml per 10 litres for the first dose and after repotting, 20ml through veg, then 5ml in flower. Add it before you correct pH, because it pushes pH up.
- Cannazym: 25ml per 10 litres from the first veg phase right through to the end. CANNA say to double it to 50ml if you are reusing your substrate, and not to mix it with hydrogen peroxide.
- Start: not on the main chart. It is the seedling and cutting feed, 40ml per 10 litres, used before you move onto the Vega or A+B.
Flowering
- Boost: 20ml per 10 litres from the moment flowers start to form, which CANNA can rise to a maximum of 40ml through flowering for extra strength.
- PK 13/14: 15ml per 10 litres for one week only, about three weeks before harvest. CANNA warn that using it for longer risks a build-up of phosphorus and potassium.
- Flush: not on the chart. 20ml per 10 litres in soil or 40ml in hydro, once a week in the last one to two weeks.
Extras
- CalMag Agent: appears on the newest charts as an every-week row. Its job is to bring soft or RO water up to a starting EC of about 0.2 to 0.4 before you add feed, at roughly 0.1 to 0.5ml per litre. Hard-water growers will need little or none.
- Silica and the Mono range: not on the chart. CANNA give Silica at 1 to 2ml per litre with every watering except the PK 13/14 week; Monos are for correcting a specific deficiency.
Step 4: Mix your feed and check EC and pH
Work in order and stir as you go.
- Fill your tank or can with water and note its EC. If it is very soft, add CalMag Agent to bring it to around 0.2 to 0.4.
- For A+B feeds, add part A, stir, then part B. CANNA say never to mix A and B concentrate together.
- Add Rhizotonic, Cannazym and any boosters for the phase, one at a time.
- Check the EC. CANNA's charts give both an "EC+" (nutrients only) and a total that assumes tap water of EC 0.4. Their own words are to add the EC of the tap water you use to the recommended EC. As a guide, the totals on the Coco chart run from about 1.1 to 1.5 at rooting up to 2.0 to 2.4 at peak flower, and on the Terra chart from 0.8 to 1.2 up to 1.9 to 2.3.
- Adjust pH last. CANNA give 5.8 to 6.2 for Terra, 5.5 to 6.2 for Coco and 5.2 to 6.2 for Aqua, and note that adding pH Down can itself raise the EC. Our meters and testers range has the pens you need.
Step 5: Start low and let the plants decide
CANNA say themselves that the chart is not an iron law. Start at the bottom of each range, especially in a first run, and move up only if the plants look hungry. If you grow a long-flowering crop, repeat the middle flowering phase rather than pushing the doses higher.
Common mistakes we see
- Forgetting to add your tap water EC to the chart figure, then overfeeding in a hard water area.
- Running PK 13/14 for more than one week.
- Using the Terra chart in coco, or Coco A+B in soil.
- Adding Rhizotonic after setting pH, then wondering why it has drifted up.
- Reusing coco without doubling the Cannazym.
- Working from an old chart. The current layout has changed.
FAQs
Is there a light and heavy feeding version?
Yes, in the online Grow Guide generator. The printed PDFs are the normal schedule, which CANNA say suits most situations.
When exactly do I use PK 13/14?
One week, in Generative Phase II, roughly three to four weeks before harvest. Then stop.
Do I need Boost?
No. Base feed, Rhizotonic and Cannazym make a complete CANNA schedule. Boost is the first extra most people add, from the point flowers start to form.
Can I use the Coco chart with another brand of coco?
Yes. The chart is for the CANNA Coco nutrients, not just CANNA's own coco. Buffered coco from another brand works the same way.
Need a hand with your schedule?
Bring your chart into our shop at Unit 2 Black Lake, West Bromwich, B70 0PJ, and we will go through it with you. You can also call 0121 553 7872 or WhatsApp us. Browse the full CANNA range online, with free UK delivery over £94.99 and price match on what we stock.