As said by the tutorial of the game, a Template:PvZHLink behind a Torchwood is a good strategy, as the Repeater is able to do a lot of damage to a zombie or a zombie hero. Other peashooting plants can substitute and even replace the Repeater, for example, the Skyshooter or the Template:PvZHLink. Additionally, Torchwood can be used as a cheap wall due to its relatively high durability for cost. Usually, the Torchwood will survive and then the player could plant a Peashooter for more damage. Black-Eyed Pea can become a very big threat with Torchwood, as it will limit the Zombie Hero for trick usage, as well as getting a very powerful plant early in the match. Unlike the firsttwo games, Torchwood can boost Template:PvZHLink's attack without thawing its ice pea, making it more powerful.
For a simple early-game deck, Torchwood is a great plant to have a few of in a deck, along with many Peashooter type plants. If you have no good plants (like early in the game or if you've used all cards in the deck) you can use Template:PvZHLink on a Torchwood as a last resort.
Against
Because of its health, Torchwood can be difficult to dispose of until later into the game. Tricks such as Nibble, Rolling Stone and Weed Spray can be used to attack the plant protected by Torchwood, or the Torchwood itself. If the player is Electric Boogaloo or Professor Brainstorm, they can use Electrobolt against this. Another strategy is to allow Torchwood to live and boost the pea plant's attack, making the pea plant vulnerable to Rocket Science and Cut Down to Size.
Additionally, you can simply move the pea plant using Sumo Wrestler or Terrify into another lane, leaving them vulnerable to attack while losing the boost they gained from Torchwood. Moving this under a pea will greatly help you too, as it can't boost the pea.