Even watering, every pot: a plain guide to the Fumer Whip Kit
Ask ten people why one pot in their room is always behind the others and you will get ten answers. Nine times out of ten it is not the nutrient, the light or the media. It is the watering.
Why hand watering drifts
Watering by jug feels controllable, and for four pots it more or less is. The trouble starts when the room grows. You water the front row first while the can is full and heavy, and the back row last when you are tired of carrying it. The pot near the door gets checked every time you walk past; the one in the corner gets remembered. Over a few weeks those small differences compound into pots at genuinely different moisture levels, which means different root development, different feeding, and plants that never quite even up.
The fix is not discipline. It is taking the decision away from yourself.
What a whip line actually is
A whip line system runs a mainline of poly tube along your bench or floor, and from that mainline a thin flexible line -- the whip -- drops into each pot with an emitter on the end. Turn the water on, every pot gets fed at once, and every pot gets the same amount.
The part that matters, and the part people skip when they build their own out of bits, is pressure compensation.
Pressure compensated, and why you care
Water in a pipe loses pressure as it travels. On a plain drip line, the emitter closest to the pump sees higher pressure than the one at the far end, so it delivers more water. On a short run with four pots you might not notice. On a sixteen-pot run you absolutely will -- the front of the row is wetter than the back, and you are right back to the problem you were trying to solve.
A pressure compensated emitter has a small flexible diaphragm inside it that opens and closes to hold the flow steady across a range of inlet pressures. Feed it anywhere in its working range and it puts out its rated flow. First pot, last pot, uphill, downhill -- same delivery.
The Fumer Whip Kit uses Netafim pressure compensated spray stakes and PC distributors rated at 12 litres per hour. That rating is the useful number, and we will come back to it.
What is in the kit
Every kit is built as a complete station per pot, plus the one tool you need to install it:
- 12 LPH Netafim pressure compensated spray stake for each pot -- UV stabilised, so it does not go brittle sitting under a light.
- 12 LPH Netafim PC distributor for each pot, which is the part doing the pressure compensating.
- Netafim 3mm whipline for each pot, cut to the drop length you choose.
- A hole punch tool, one per kit, for tapping clean outlets into your mainline.
The punch matters more than it sounds. A clean punched hole seats the barb tightly and does not weep. A hole made with a screwdriver or a drill bit tears the poly and you will be chasing that drip for months.
Picking a size
Kits come in 4, 8, 16 and 32 stations. Count pots, not plants -- if you run two plants in one large container you still only need one station, though on anything over about 30 litres a second stake on the far side gives you a much more even wetting front.
- 4 station -- propagation benches, mother plants, a small tent.
- 8 station -- the usual answer for a single tent.
- 16 station -- a large tent or a small room.
- 32 station -- full rooms and multi-bench setups.
Running more than 32? Talk to us, we build larger configurations to order.
Picking a whipline length
This is the drop from your mainline to the surface of the media, and it is the measurement people get wrong. Measure it before you order rather than after.
- 40cm -- mainline close to the pots, low benches, tight spacing.
- 55cm -- the all rounder, and the right answer for most tent layouts.
- 65cm -- taller benches, big fabric pots, wide canopies.
Slightly too long is fine, you can coil the excess. Too short and you are re-routing your mainline.
Working out your flow and run time
Here is where the 12 LPH rating earns its keep. Multiply stations by 12 and you have your system flow in litres per hour.
- 8 stations = 96 litres per hour = 1.6 litres per minute across the whole system.
- 16 stations = 192 litres per hour.
- 32 stations = 384 litres per hour.
Per pot, each stake delivers 200ml per minute. So if you want 500ml into each pot, that is a two and a half minute run. Set your timer from that number rather than guessing, and you will know exactly how much went in without weighing anything.
Two things to check before you commit: your pump needs to comfortably exceed the total flow at the head height you are lifting to, and your reservoir needs to hold a full irrigation event with room to spare.
Installing it
- Lay your mainline where it will sit permanently and let it relax in the warmth for half an hour so it stops trying to coil.
- Punch an outlet above each pot.
- Push the distributor barb into the punched hole until it seats.
- Connect the whipline to the distributor, and the spray stake to the other end.
- Push the stake into the media, angled slightly so the spray pattern falls across the pot rather than down a single channel.
- Run the system with the stakes out of the pots first to flush swarf and dust through, then set them in.
Keeping it working
An inline filter on the feed is the cheapest insurance you will ever buy. Most emitter blockages are not scale, they are undissolved nutrient or a bit of media that got into the reservoir. Flush the lines with clean water between crops, and if you run heavy organic inputs, flush more often -- biology is wonderful in the root zone and a nuisance inside a 3mm line.
Check your stakes every couple of weeks by watching a run start. A blocked one is obvious the moment the water comes on.
Get one
The Fumer Whip Kit is assembled here in Australia from genuine Netafim components, and starts at $25.97 for a 4 station kit. Come and see one built up at the shop on Ipswich Road if you would rather have a look before you buy -- we can walk you through sizing it for your room in about five minutes.
Also worth a look: our irrigation and plumbing range for mainline, fittings and filters.
