Transplanting Cannabis Seedlings

Transplanting Cannabis Seedlings is a root job, not a date on a chart. You move a marijuana plant when the plug holds together in your hand. A weed auto does not take that trip. It starts in the pot you mean to finish, because its clock does not stop while the leaves sulk. Everything else in the work is how you keep the root hairs you already grew.

Transplanting Cannabis Seedlings

The move is simple to describe and easy to botch. A plant that has been living in a cup, a cell, or a starter cube goes into a larger volume of mix. You are not upgrading the plant. You are giving the roots a next room before they turn into a circling mat, and before you drown a tiny plug in a tub of wet mix. The plant on the cube, tag still on the stem, is ready to be carried by that cube. The stem is not a handle.

Direct sowing skips the job. The seed goes into the pot you intend to keep, and you never tip a cup. That is the right call when you do not want to move anything, and it is the default for an autoflower, which has its own section below. A photoperiod can spare the days. It can live in a small cup while you learn which plant is worth the finish pot. The seedling stage is the diary of that small plant. This page starts when you are deciding whether the cup is finished.

Two seeds started the same morning are not the same plant two weeks later. One throws roots to the drain holes. The other is still a polite tuft. You move the one whose ball holds. You leave the other in the cup. Potting them as a pair because they share a birthday is how the slow one gets buried in a wet pot it cannot occupy, and how the fast one sits an extra week and starts to circle.

A cutting in a cube follows the same test as a seedling in a cup. White roots through the cube, the cube holds, you move the cube. Do not peel the cube apart to make it look like a seed-grown root. The cube is the ball. How the cutting was taken sits on the clone page, and it is a different job from the move.

Roots decide, not the calendar

Tip the container. A ready plug comes out as one piece and keeps its shape in your palm. White roots at the edge of the mix, or roots poking the drainage holes, are the signal. Leaves that reach the rim, and two or three sets of true leaves past the round seed leaves, are only hints. In a warm room those hints often land between 10 and 21 days after the sprout stood up. A cool room, down around 20 C, can add a week. A chart that says day 7, or one that says four weeks, is describing a room you do not have.

The day by day notes walk the leaves one morning at a time. Use them to see what a healthy top looks like. Do not use them as a move alarm. The top can look ready while the roots are still a few threads that fall apart when you tip. The top can look small while the cup is already a white web. The cube in front of you is that second case: roots packed on the face of the plug, which is a ball, not a birthday.

The first round pair are seed leaves. They do not count as a set. The first serrated leaves are set one. A move at the seed-leaf stage gives you a thread of root and a smear on the bench. Wait for a ball that holds. If the cup has one drain hole, the bottom stays wet and the roots knot around that puddle. A few extra holes, cut before you sow, keep the test honest.

Water about a day ahead of the move. The ball should be moist enough to hold and dry enough to slide, like a wrung cloth. Soup slumps and tears the hairs. Dust cracks, and the hairs leave with the crumbs. If it crumbles, it was early or bone dry. Water it and test again in a few days. If the bottom is a hard spiral with almost no mix left between the roots, it was late. That brick belongs to the root bound page. Teasing a net apart, or a shallow score on a hard brick, lives there. Do not turn a clean move into that repair.

A long pale stem is not a signal to pot up. It is a signal the lamp was too far, or the plant was reaching for a window. A bigger pot does not shorten the stem. The seed light page owns how far the lamp sits. You can set a stretched plug a little deeper so mix supports the stem, without burying a single leaf. Then fix the light. If you only bury the stem and leave the lamp wrong, the next stretch of stem does the same thing.

Lift the plug, do not pull the stem

Catch the ball. On a solo cup, squeeze the sides, tip, and let the mass slide into your other hand. If it hangs on, cut the cup down one side and peel the plastic away. On a cell tray, push up through the drain hole. On a rockwool cube or a peat plug, pick up the cube. It already is the ball. Write the name on the tag before you tip. Five cups become five anonymous pots once the mix is on your hands.

Do not pull the stem to help the cup let go. The stem will come out. The roots will stay behind, or they will strip on the way. Either way you have a plant that cannot drink. Do not rinse the roots under a tap to get a look. Do not shake the mix off a ball that is not circling. The fine hairs are the part that takes up water, and they are the part a rinse destroys. If the roots are a loose net inside mix that still looks like mix, leave them alone. Set the whole piece in the new hole.

A tight spiral means you are late. The root-bound page is where that net gets teased and where a hard brick gets a shallow score. If the ball holds and the roots are only at the edge, you are on time. Stop inspecting.

The new mix should already be in the room, not in a cold garage. Cold wet mix stalls the roots you just moved. Wet it the day before until it is damp through, then let it drain. Mud is wrong. Powder is wrong. The same wrung-cloth test you used on the plug works here. Seat the plant with the water it has already been drinking, not a new solution you felt like trying.

Dig a hole a little wider than the plug. The top of the plug sits level with the new surface, or about a finger lower if the stem is stretched. Do not bury a leaf. Set the plug in, fill around it, and press with your fingertips until the new mix touches the old ball on every side. A gap becomes an air pocket and the hairs dry out. A fist that squeezes the air out is the other failure. Mix goes all the way to the drain holes. A layer of rocks only raises the wet line. Water slowly around the plug until the new mix darkens and a little water shows at the drain, then stop.

Step the pot, do not drown it

Step about twice the volume. The empty pot beside the cube is the next room, not a storage tub. A tiny plug in the middle of a large wet mass does not have room to grow in any useful sense. It sits in mix the roots have not occupied, and that mix stays wet because nothing is drinking it. Roots need air as much as they need water. A swamp around a plug is how you stall a plant that was doing fine in the cup.

A solo cup is on the order of a pint, under half a litre. Twice that is a quart to a half gallon, about one to two litres. The next step, still in veg, is about twice again. A home photoperiod that is not being grown into a tree often finishes in 3 to 5 gallons, about 11 to 19 litres. A closet plant in a 7 or 10 gallon pot spends flower wet in the middle. Outdoor plants want more room. The step that travels is the same: about twice, while the plant is still in veg.

A fabric pot air-prunes tips that hit the wall, so the spiral is slower. It does not shrink the litres. A one-gallon fabric pot is still a one-gallon pot. A jump from a plug into the finish pot works only when you water the island around the plug first, then widen the wet zone as the roots walk out. Soaking the whole tub on day one is the usual failure. If you will not water with that restraint, take the smaller step.

Put the plant in its last pot at least a week before you flip to 12 hours, and two weeks is kinder. Roots should be walking the new mix before the plant spends itself on flowers. The vegetative stage is where that growth lives. Finish the container while you are still there. On a small fabric pot, a pot that goes light in a day is occupied. Do not tip it out to admire the web.

Autos finish in the first pot

An autoflower does not have a veg switch you control. It starts a countdown near the time it sprouts, and it will flower on that countdown whether the pot is ready or not. Shock does not pause the clock. A week of droop is a week of the only veg that plant was going to get. That is why the auto starts in the finish pot, or why you sow it there and never move it. The autoflower grow is the rest of that plant. This page only needs the one rule: do not plan a series of cups for a plant that cannot spare the moves.

A photoperiod can wait, because you choose when veg ends. It can live in a cup, step to about a gallon, then step to the 3 to 5 gallon, each move about twice the volume, and replace the sulk with new growth before you flip. That clock difference is the photoperiod and autoflower comparison. If an auto is already in a cup and the roots are at the edge, move it once into the finish pot and stop. A second move costs more days than the first.

A small plant in a large pot looks silly for a week. Water the small wet island around the stem. Leave the outer mix damp from the day-before prep, not flooded, and widen the watering as the leaves spread. One plant in that pot. Two plants means you cannot pull the loser later without tearing the one you want.

Shock is a day, not a disease

A clean move can still droop. The leaves go soft the afternoon you pot up, and they stand back up the next day or the day after. Water is moving through hairs that got bruised even when you did the lift right. That droop is not a deficiency, and it is not a disease you spray. A feed will not stand the leaves up. A heavier bottle the same day puts salt into mix the roots have not occupied, which burns the hairs you have left.

Give it plain water. Skip the feed for a couple of days, until the leaves have stood up and the new mix has actually been drunk. A B vitamin pour does not stop the droop. The plant makes its own, which is the point of the B vitamins page, and a bottle is not a tool for this hour. A kelp bottle is a feed. It is not the move, and it does not belong in the same watering can as the seating water. A rate would be a different page. This one does not have one.

If the plant is still flat on the third day, stop adding things and look at the three causes that actually show up. You tore the ball, usually by pulling the stem or by tipping soup. The new mix is a swamp, usually because the pot was too big and you soaked all of it. Or the lamp is now too close, because the plant sits higher in the new pot, or because you set the pot on a stand, or because a stretched plant is closer to the lamp than it was yesterday. Ease the lamp for a day. The seed-light page already has the distance. Do not invent a new brightness number while the plant is limp.

A humidity dome goes back on only for a very young seedling that just came out of one, and only when the room air is harsh. A plant with several sets of leaves does not go back under a closed dome. Wet, still air trades a day of droop for a fallen stem. Yellow lower leaves after a late move usually mean a dry brick inside a pot you are watering at the rim, or roots that were already circling. Plain water is the fix you still have. A new bottle is not.

You know the move worked when a new leaf starts at the top, not only when the old leaves stand back up. Standing up means the plant can drink. A new leaf means it has started spending again. If it stands and then sits still for a week, the mix is still too wet or the lamp is still wrong. A wet pot on a cold concrete floor stalls the same roots. Set it on a tray. Aim a hard fan at the wall for a day so it does not dry the plug.

Do not move a plant in flower

Flower is the wrong week for a new pot. The plant is spending sugar on calyxes and pistils. A move spends that sugar on roots, and the flowers stall while the leaves droop in the exact stretch you wanted them working. Finish the last pot a week or two before you flip. Then leave the pot where it is. The flowering stage is the work of those weeks. None of that work is sliding a root ball into a tub because the plant looks hungry for room.

The exception is a plant that is collapsing because the pot is a brick and you cannot get water into it. That is a rescue, not a plan, and the rescue write-up is the root-bound page. Do not schedule a flower move because someone said the plant will take off if you give it fresh mix in the middle of flower. It will sulk. You do not get those days back, and the pistils do not pause while you fuss with a pot.

If you already flipped and the pot is only snug, live with the snug pot. Water a little more often, in smaller amounts, and keep air in the mix. A snug pot in flower is a watering problem. Digging the plant up is a bigger one. Roots that are a little tight will still finish a crop. Roots that you tore while the flowers were swelling will spend the swell rebuilding instead of filling out. Leave the fabric pot, the plastic pot, and the plant in the corner you already chose.

One move, then leave it

Count the moves before you start. A photoperiod might take two steps and a finish pot. An auto takes one pot and no steps. After the plant is in the container you mean to finish, stop. Every extra move is another day or two of soft leaves and another chance to strip the ball. The plant that has stayed put and put on leaves is done traveling. Let it fill the volume. Do not check the roots a week later by tipping it out again. You already did the inspection when you moved it.

The bigger pot stays wet in the middle longer than the cup did. If you water on the old schedule you will swamp it, and if you wait until the top looks like the old cup you may still have a wet core. Lift the pot. A light pot gets water. A heavy pot waits. The ongoing rhythm, including how it changes once flowers start, is the water page. This page only needs you to throw out the cup rhythm on the day you step up.

Direct sowing remains the honest option when you do not want this job at all. One seed, the pot you mean to finish, no tip, no seating water, no afternoon of soft leaves. You trade away the chance to cull a weak seedling before it takes a big pot. You gain a root system that never got interrupted. For an auto, that trade favors sowing where it will finish. For a photoperiod in a small tent, a cup still earns its place, because you can watch a few candidates in the space of one finish pot and move only the one you are keeping.

That last point is also the legal one, and it is easy to miss when the cups look too small to count. In Canada the cap is four plants per household, not per adult. Quebec prohibits recreational home growing. Manitoba has allowed indoor growing only since 1 May 2025, and the age there is 19. A seedling counts. A tray of extras, started so you can pick a winner after the move, still counts. Do not start that tray. The order of the rest of the grow, from the seed you actually keep through to harvest, sits on the 10 steps page.