Why Your 400w hps ballast Still Matters for Growing

If you're setting up a mid-sized indoor garden, choosing the right 400w hps ballast is probably the most important technical decision you'll make for your plants. While a lot of people have jumped ship to LEDs lately, plenty of us still swear by the classic intensity and spectrum that High-Pressure Sodium (HPS) lights bring to the table, especially during the flowering stage. But the bulb is only half the story; without a solid ballast to kickstart that arc and regulate the current, your expensive bulb is basically just a glass paperweight. ...

May 8, 2026 · 7 min · Cosette Long