From Ground: First, water the dahlia 'Nuit d'Ete' plant to dampen the soil. Then, dig a wide trench around the plant using a shovel or spade, ensuring the plant's root ball remains intact. Carefully work the spade under the root ball to lift the plant from its original location.
From Pot: Start by watering the dahlia 'Nuit d'Ete' plant well a few hours before transplanting. Gently tip the pot on its side and carefully slide the plant out, supporting the stem with one hand. If the plant is root-bound, you may need to gently loosen the roots with your fingers.
From Seedling Tray: Water the seedlings beforehand. Use a hand trowel to gently lift each dahlia 'Nuit d'Ete' seedling from the tray, being careful not to damage the roots. Handle the seedlings by their leaves rather than the stem to avoid crushing the delicate stems.