Drosera Leaves Turning Black From Tips to Base?

[Not a Number]

If you never repot your plants the media breaks down in as little as 1 year depending on the quality of the media, water, watering practices and other environmental conditions. Drosera in particular show many of the same symptoms you describe beginning after the 2-3 year mark with old media. And yes they will eventually die.

 

[Plant Planter]

Yeah, repotting is a really good idea after a while. If you don't do it often enough (every one or two years) the soil can break down and your plant's roots can become crowded, although that's pretty uncommon for carnivorous plants...

 

[SgtSarracenia]

The soil quality could be one of the major factors affecting the die back of your dews, but I truly feel you should have a 50/50 mix. Peat : sand or perlite

Drosera cannot all be treated the same though. D. intermedia for example like to grow in water logged media, while others not so much.

The reason they are growing far better in the Sphagnum is because the roots are being aerated and not being suffocated by such a dense medium.

Like I told the kids when I did the 6th grade presentation earlier this week, put water about 1/4 of the way up. So when you touch the top of the media it feels wet, but not like a sponge. Maybe you should rethink getting anymore Drosera until you get the problem solved. I would hate for you to continue killing plants unnecessarily.

 

[Not a Number]

D. aliciae - here's some of the weird things that can happen when the media is old and breaking down. Note the thin dead leaves around the strange structure: