The large amount of zombies should not discourage the player. The focal point of this level is to stall the zombies as much as possible using Hurrikale.
The main damage outputs in this level are Spikeweeds, which work the best way if their use is synchronized with Hurrikale. Two Spikeweeds should be placed next to each slider tile, except during the last wave when the player should accumulate all the zombies in the topmost row and then place as many Spikeweeds as possible.
The placement of Peashooters and Repeaters is not important. Ideally, Repeaters should be planted in the top two squares of the first column, as only one peashooting plant is viable in that row.
The small number next to the zombie icon means that zombie will always appear in that lane, with 1 being the topmost lane and 5 being the bottommost one.