Try to use another copy(or all three if possible), then you can double the amount of damage you can inflict.
The best way for this card to build up counters is to use "Rose Lover" effect to special summon "Lonefire Blossom" (from your hand), then use its effect to special "Gigaplant". With this you can normal summon "Gigaplant" and with its effect special summon "Lonefire Blossom", then reuse its effect to summon another plant-type monster. This will easily maximize the amount of counters on this card.
Do this combo for easy damage:"Lonefire Blossom" → "Evil Thorn" → use Thorn's effect. This results in no loss in card advantage and gets out an extra monster.
If you have "DNA Surgery" on the field with "Plant" Type designated, various search monsters will generate Counters very quickly, which increases the chances of using this card's max effect.