Hop latent viroid is the reason a room full of healthy looking plants can quietly stop performing. It is the single most expensive thing a grower can be sold, and it almost always arrives on a cutting.
An infected plant does not fall over. It grows shorter internodes, thinner leaves and looser flower, it drops trichome density and terpene load, and it gives up somewhere between ten and forty percent of the yield you were expecting. Growers call it dudding. You usually find out in week six of flower, months after the cutting went in, and by then it has moved through everything that shares water, tools or hands with it.
The hard part is that it is asymptomatic for a long time. A mother can carry it, look perfect, and put out infected cuttings for a year. You cannot see it, and neither can the person selling it to you.
Every mother in the building is lab tested for HLVd. We do not take a cutting off a plant that has not come back clean. A mother that tests positive is destroyed, not quarantined, not run out for one more round and not quietly sold off.
Testing the mother is the only point in the process where catching this is cheap. After that it is your electricity, your light hours and your season paying for it.
We test mothers, not every individual clone, and no nursery on earth tests every cutting it ships. What we are telling you is that the plant your cutting came off was tested and came back clean, and that we do not run untested stock. We are not going to dress that up as a guarantee about what happens after the box leaves us, because once a plant is in your room it is exposed to your tools, your hands and whatever else you brought in.
The habits that matter are unglamorous. Sterilise blades between plants rather than between batches. Quarantine anything new for a couple of weeks before it touches your mothers, including cuttings from us. Do not share reservoirs between a quarantine area and your main room. If a plant ever duds on you, test it before you convince yourself it was the feed.