Sure thing. Start by using a directional light with a cosine falloff instead of the hard-edged Unity default. Then add a simple shadow map bias tweak—half a texel is usually enough to kill the acne. For the sun itself, use a second, slightly smaller directional light with a very high intensity but a low ambient contribution; that gives the glow effect without the halo. Finally, clamp the light color to a 0.9 max value so the white doesn’t bleed through the leaves. Happy growing!