Nearly all my tanks have been sand and/or gravel substrate, and tons of the plants have done fine even when I was very forgetful about adding root tabs or liquid ferts! Even the ones that appreciate a root tab (and some cheaper, but name brand root tabs, like Tetra or API brand ones, are still good! Just avoid any random, non-name root tabs since they can release too much of any random thing that's been added into the water column. Had that with cheap, non-name brand root tabs from amazon once, as did someone else here recently). But for ones that appreciate a root feed, like crypts, swords, vallis... they can provide a really get good "stick a tab or 1/2 a tab under their roots and forget for the next six months" boost!
Will be adding some photos to my own threads later, because today I snapped some photos of the plants that have survived my neglecting them with zero ferts, root tabs and not much light either over the last two years! One is a massive crypt, an offshoot of ones that I inherited from my dad's tank, were cut down to nothing but roots at one point because of persistant black algae but grew back from nothing but roots, and I've had various plants from them since then. About two years ago I scooped this one crypt plant into a cup as I tore down the main tank and didn't want to disturb the roots of my established plants too much. It's been a shady corner of my darkest, oldest tank now with no extra ferts in just a cup of plain sand, cheap and later malfunctioning Nicew light bar, but the crypt looks amazing, is bursting out of the cup, and will easily split into several small plants once I unpot, split and replant it.
Even if it does a crypt melt, which this one hasn't usually, I know it'll be back! Crypts are brilliant like that, they're greedy root feeders and can put out some amazing root systems and fast growth if given the chance, but also super forgiving in lower light, less ferts, and will just keep chugging away, and coming back even if you wind up having to cut them back to nothing but roots.
My crinum had root tabs when I first got it, but it's been in the same boat as the crypt for the last two years, in it's own cup of no ferts added sand, looks wonderful and I just measured the longest leaf at 42 cms/3.5 FEET!
I'll upload the photos of those two I just took in a min
Have three types of java fern that are also still doing well, the normal, the narrow leaf, and the twisty windlov types, all coping just stuck into spots of hardscape or left to float and do their thing, producing baby plants and plugging away.
This tank hasn't had ferts added yet, Argos play sand, Nicrew lightbar, nothing fancy, nothing but pleco poop, but in two weeks the plants went from this:
to this: