Aptus Startbooster vs Topbooster: when to use each
Startbooster supports roots and vegetative growth; Topbooster is for flowering. Compare doses, timing and practical considerations for reservoirs and drip systems.
Two boosters with different jobs
Startbooster and Topbooster are organic supplements in a feeding program. Startbooster is aimed at root development and vegetative growth. Topbooster is intended for flowering. Choose by plant stage and feeding chart, rather than the shared word in their names.
Startbooster and Topbooster supplement base nutrients. With Startbooster on sufficiently prefertilised soil, extra growth feed can temporarily be unnecessary. Assess the nutrients already in the medium first; this does not automatically apply to coco, hydro or depleted soil.
When should you use Startbooster?
Use Startbooster during vegetative growth and the first flowering week. The standard dose is 2.5 ml per 10 litres, equivalent to 0.25 ml per litre. In the AH20 programme, early flowering uses the first watering. Consider developmental stage and application frequency together.
Add Startbooster after mixing the mineral nutrients and carrying out the EC step. Increasing the amount does not replace a suitable base feed, growing medium or watering routine. Follow the dose on your label and the selected program.
When should you use Topbooster?
Dose Topbooster at 2 ml per 10 litres from the second through the last flowering week. This equals 0.2 ml per litre. Use alongside NPK base nutrients and match the final application and any flushing stage to your programme.
Topbooster is also different from Super-PK, a separate phosphorus and potassium supplement. Do not automatically add extra PK because you are using Topbooster. Check the combination and total nutrient supply within one feeding chart.
A calculation for a 20-litre reservoir
Startbooster at the standard instructed ratio: 5 ml in 20 litres at the specified application times.
Topbooster at the standard instructed ratio: 4 ml in 20 litres during the specified flowering stage.
These are separate conversion examples, not advice to apply both products together. Use the development stage and application frequency in the chosen Aptus chart to determine the transition.
Consider the reservoir and drip lines
Organic material in Startbooster and Topbooster can contribute to biofilm and blocked drip lines. Use System-Clean in a suitable drip programme and keep the lines clean. Store mixed nutrient solution for no more than two to three days and prepare only the amount needed within that period.
Consider whether a mineral Clean program better matches an automated irrigation setup. An organic booster changes the composition of the solution. Storage advice from another product combination does not automatically apply.
Compare sizes and check what you already use
Startbooster and Topbooster are available in 250 ml, 500 ml, 1 litre and 5 litres. Choose according to the solution volume used during the relevant stage. At their standard doses, the same water volume uses more Startbooster than Topbooster.
Assess base nutrients, Regulator and any PK supplements as one feeding programme. An additional booster should have a clear purpose. Avoid several supplements adding the same nutrients without accounting for the total.
Products in this guide
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