When to switch from grow to bloom fertiliser (plant-by-plant guide)
Switch from a grow (nitrogen-led) feed to a bloom (phosphorus and potassium-led) feed the moment a plant starts forming buds or flowers. For most Australian gardens that is mid to late spring. Keep anything purely leafy (lawns, hedges, spinach, herbs) on the grow feed all season; they never switch.
Two-phase feeding sounds technical, but the trigger is something you can see with your own eyes: buds. Here is exactly when to make the change, plant by plant.
The one visual rule
While a plant is building leaves, stems and roots, it wants nitrogen: that is Medigrow, phase 1. The moment it begins reproducing (buds, flowers, fruit forming), its chemistry shifts toward phosphorus and potassium: that is Medibud, phase 2. You do not need a calendar, just a weekly look at the plant. First buds visible = switch on the next feed.
When each plant typically switches
| Plant | Switch to bloom feed |
|---|---|
| Tomatoes, chillies, cucumbers | First flower trusses (late spring) |
| Roses | First bud set after spring flush of leaf |
| Citrus and fruit trees | Blossom, through to final harvest |
| Strawberries | First flowers (early to mid spring) |
| Flowering annuals (petunias, marigolds) | 2 to 3 weeks after planting out |
| Spring bulbs | As flower spikes emerge |
| Lawns, hedges, leafy veg, herbs, ferns | Never; stay on the grow feed |
Running both feeds at once
Most gardens are in both phases at the same time: the lawn and the hedge stay on phase 1 while the roses, tomatoes and lemon tree move to phase 2. That is normal, and it is exactly what the Whole-Garden Bundle is for: one watering can of each mix on the weekend covers the entire yard. Both feeds mix at the same 2.5 mL per litre, so there is nothing new to remember.
Switching back
When flowering or harvest finishes, return the plant to the grow feed (or rest it over winter). Fruit trees in particular appreciate a nitrogen-led feed after harvest to rebuild before the next season. The full seasonal loop is in the month-by-month calendar.
Common questions
What happens if I never switch?
Staying on nitrogen gives you lush foliage and disappointing flowers and fruit. Staying on bloom feed year-round undernourishes the leafy growth phase. The switch is the whole trick; the NPK explainer covers the chemistry.
Can I mix the two feeds together?
Keep them separate and simply feed the right plants with the right can. It keeps the ratios honest and the routine simple.
Is there a wrong time to switch?
Switching too early is harmless but slows frame-building. Switching too late is the common error; if buds are already open, just switch on the next feed.
Put it into practice
Medigrow builds growth, Medibud brings the bloom. The bundle covers the whole season from 38c a feed, backed by the 30-Day Growers Guarantee.
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