For modern homes, simple geometric shapes like balls, cubes, or spirals work best. These shapes create a calm, balanced look that frames your entrance beautifully. Ball topiary gives a soft, timeless feel, while spirals and cubes look more structured and architectural. Always choose a pair of matching plants to keep the symmetry. If your doorway is tall, go for slender forms like spirals or lollipops. If it’s wider, rounded balls or cubes will look more grounded and complete.