Plants in gravel-only substrate?

you can plant any hardy low light plant in your tank ... hornwort, java fern (don't bury the roots on this one, attach to rocks or driftwood) and java moss would be fine ... anubias would be good and they are very hardy and readily available ... amazon swords are also hardy and nice looking plant ... just plant them in the gravel like the gravel is soil ... most aquatic plants will do perfectly fine growing in gravel only ... i would suggest a fertilizer ... with a fertilizer your plants will thrive and without not so much ... you can buy fertilizer that you push into the substrate or you can get liquids that you add after a water change ... if you have live plants, it is a good idea to put a new bulb in every year ... you don't really need any high tech plant bulb, just a regular bulb, but your plants will do better with a newish bulb ...