A rose is just as beautiful the second and third time it blooms as when its petals open up for the first. It's no less exciting to see the phenomenally fun tactical gameplay of Plants vs Zombies pollinate another platform.

PopCap has cultivated it with great care, not only proving to be skilled at game design but also attuned to the nuances of portable play.

Plants vs Zombies is a near-perfect tactics game - only a couple of minor setbacks wilt the tips - with challenges that will eat at your brain and humour cementing it a spot in your heart.

Get off my lawn

The tactical challenges aren't the only thing that will absorb your noggin - zombies want it too. Holed up in a quaint suburban home, you're forced to wage war against the encroaching undead hordes.

Plants are your weapon of choice. Each level plays out on a grid with your house situated on the left and zombies ambling in from the right. You're free to plant anywhere on the grid, so long as you prevent any one zombie from breaking into your home. A row of lawnmowers serves as a last line of defence, though once triggered they're gone for good.

You begin by defending your front yard at high noon, using sunshine to cultivate a range of defensive plants. Each ray of sunshine amounts to 25 points that can be spent on plants, which vary in cost according to their potency. There's also coins that enable you to buy new plants and upgrades when collected from decapitated zombies.

Unnatural botanicals

Several dozen varieties can be planted from explosive potato mines and pop-shot pea shooters to spike-spitting cacti and pervasive fume-shrooms.

There's a staggering number of species to counter an equally diverse zombie population - bucketheads, football players, bobsled teams, even dolphin riding zombies. You're constantly acquiring new plants and encountering different enemies throughout the 50-level Adventure mode.

The environments change, too. From the simple green expanse of the front lawn, the battle between plants and zombies moves to the backyard where a swimming pool makes cultivation thorny.

Nighttime levels affect the production of sunshine for plants, forcing dependence on sunflowers and sun-shrooms for precious light. A final stand on the roof requires use of pots in lieu of soil.

Such variety ensures tactical depth, while at the same time the simplicity of the game's core mechanic makes it accessible. Drag-and-drop controls and an uncluttered interface guarantee hassle-free gameplay. Easily understood plant and zombie types with appropriate visual cues make strategising a snap.

Soiled

If anything, the number of plants and zombies borders on the overwhelming. The ability to pick and choose a handful of plants per level encourages general strategy, but it also results in certain types consistently getting passed over or rendered obsolete as better plants are unlocked later in the game.

The sheer number of plants is a problem when viewed from another angle: technical performance. Plants vs Zombies exhibits significant slowdown whenever you've filled the screen with plants. It doesn't ruin the experience, but obviously sullies the presentation.

Replay value is fairly high, even though the game ditches a number of modes - Survival, Puzzles, and Zen Garden modes are all out. Instead, you're granted access to a Quick Play mode once you've complete the lengthy Adventure. A short list of achievements also encourages extended play, but without integration to wider social gaming network such as OpenFeint or Plus+ their value is limited.

This version is a seedling compared to the more expensive PC version, yet in all fairness that does nothing to diminish the quality of gameplay. Plants vs Zombies has deep tactical roots that ensure this second blooming on iPhone and iPod touch is just as fun.