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There ’s something profoundly rewarding about nurture a lilliputian ejaculate into a thriving plant . But when a plant life outgrow its container , pot up can seem daunting . Fortunately , with care and a distich of condition , potting up is easy and will help to keep your plants happy !

In this post , we will explicate the welfare of potting up and how we do so here at Heritage Farm . We will also show you when and how to pot up your seedlings , and give you some helpful tips . Whether you ’re a first - fourth dimension gardener or brushing up on your green ovolo skills , this guidebook will facilitate you set your seedling up for succeeder .

A tray of 3-inch pots, each with a hole and a small tomato plant in the center.

Potting up tomato seedlings at Heritage Farm

What is “potting up”?

pot up is the process of move a plant up from one size of a container to a large size as it ask more space to grow .

Usually , pot up is only a common pattern for crop that have an extended germination period or spend a longsighted time growing in the greenhouse , such as :

Why should I pot up my seedlings?

Simply put , potting up seedlings will allow them to turn into large , good for you , and happy industrial plant . Caring for indoor seedling is a fragile mental process , and young plant are sensitive to their surround .

As a seedling grows big and occupies more and more quad within its tummy , it can begin to get crowd . crowd create various problems for the works :

Giving your seedlings a larger container if they need one decoct stress . This assist them rise strong roots and prow . It also promote the plants to grow shaggy-coated rather than marvellous .

A person potting up several tiny tomato seedlings

Potting up tomato seedlings at Heritage Farm

Why not sow seeds in a larger container to begin with?

If you garden on a minor weighing machine and are n’t worried about run out of indoor space , get semen in larger container is perfectly okay ! However , there are jeopardy with sowing cum into potentiometer that are too large .

When starting seed indoors , it ’s of import for the size of the seedling to roughly match the sizing of its pot . This has to do with water management . As you irrigate the seedling , the pee saturate the soil . The water that soil draw farewell in two means : dehydration or transpiration by the plant life .

If a seedling is too small for its container , its lilliputian roots can only take over a little bit of the water . Most of the grease in the potty last out saturated and will not dry out out . This can lead to solution decomposition , yellowing leaves , stunted outgrowth , mould , and disease .

8 plant trays, each with 20 rows full of tomato seedlings, arranged in a greenhouse

We use 20-row trays used to grow tomatoes on a large scale for the farm.

Potting up at Heritage Farm

On a bigger scale , pot up helps with infinite and resource management . Here at Heritage Farm , we arise thousands of seedling in our greenhouses each fountain . At this large scale , we take to plan our glasshouse space expeditiously to avoid running out of way .

For object lesson , this year , we uprise 1,300 tomato industrial plant and sowed the tomato seeds in “ 20 - row ” trays . These trays each have 20 small rows , which can each fit 20 - 30 tomato seeds . A whole 20 - words tray can therefore fit upwards of 600 tomato seedlings .

A tray of the same size of it can only fit 32 3 - in pots . The same 600 tomato seedlings in 3 - in pots would demand upwards of 19 trays , and a whole draw of greenhouse quad .

Several large trays holing many 3" plastic pots, each with a tomato seedling

Growing tomatoes in larger pots takes up significant space.

Starting seed in small sens also help to palliate the challenge of low germination . If a tomato mixed bag has low sprouting and some seeds do n’t evolve , this wastes the space and resources used to set about those seeds .

When produce tomato plant in 20 - row trays , an instance of lowly sprouting might only emaciate a few square inches of greenhouse space . If we had planted tomato seed in separate 3 - inch pots , a few substantial inches would turn into half a tray of wasted space , grease , and water .

When should I pot up my seedlings?

Look for these signals to cognise when to pot up your plant :

True leaves : An easygoing way to tell whether a seedling is ready for potting up is to look for true leaves . When a seedling germinates , it produces its first set of foliage , called cotyledons , from the fabric within the seed . These leave-taking often bet quite unlike from the leave that the works continues to originate .

The 2d set of leaves that the works produces is the first of its “ straight ” leaf . The plant will grow truthful leaves for the relief of its life . Once a seedling has at least one or two sets of true leaves , it can handle the focus of pot up .

A 20-row tray of tomato seedlings in a greenhouse, with a bare patch of soil in the middle

This case of low germination only wasted a few square inches of greenhouse space.

emerge roots : expect beneath the toilet . When a plant life outgrow its kitty , often ( but not always ) the works ’s ascendent will begin to grow out of the crapper ’s drain holes . If you see any solution growth outside the pot , the plant call for a larger blank space to grow .

have got shape : cautiously remove the seedling from its pot . The seedling ’s roots should hold the shape of the medium well . This indicates strong etymon growth and that the plant can handle the potting - up process .

Watch this video to learn when to pot up tomato seedlings:

How to pot up seedlings

Step 1 : Water your seedling in the cockcrow of the day you plan to pot up , saturating the seedling ’ roots . Saturated root serve mitigate the shock of transplanting .

verify the aerial part of the plant ( such as the stem and leaves ) are dry to help prevent damage when handling .

Tip!Just liketransplanting seedlings out of doors , judge to pot up on a Clarence Day where the conditions is overcast . This will help the beginning stay moist .

A drawing of a small seedling with its leaf, cotyledon, and hypocotyl labeled.

Pot up seedlings once they grow their first pair of true leaves.

whole step 2 : Gather your raw containers and some potting intermixture . check that your container of choice have drainage holes .

Your grunge mixture should be plenteous in compost or other organic matter to give the seedling an extra boost of nutrient . The dirt mix should also be damp , but not too wet , and should not drip when squeezed .

Step 3 : satisfy the newfangled pot with filth and create divots in the marrow , keeping in idea the size of it and depth of the seedling .

A small tomato plant with one set of cotyledon leaves and one smaller set of emerging true leaves.

This tomato seedling is starting to sprout its first set of true leaves.

Step 4 : Carefully remove the seedlings from their one-time pots . If you have only one seedling per corporation , it is unnecessary to disturb the roots unless the flora is very root - bound .

If you have more than one seedling per stool , gently tease apart apart their roots and separate the plants . When teasing flora apart , some roots will break , and you may hear some pops and tears . These sounds may alert nurseryman , but as long as the seedling have their master root attached to the stem , they will be fine .

gradation 5 : cautiously localise the seedling into the divot in its new pot and cover its roots with soil . Gently throng the soil around the stand of the plant , but do n’t be afraid to utilize a niggling pressure . This helps prevent air house of cards beneath the surface , ensuring honest grime - to - root physical contact .

A hand holds out a small block of three tomato seedlings joined together

These roots of these tomato seedlings are holding their form, a good indicator that the plant is ready for potting up.

A note on planting depth :

Lycopersicon esculentum , like eggplant bush and pepper , benefit when imbed deeper than the soil line . Along a tomato seedling ’s stem are tiny nodes that have the potency to break into adventitious roots . Plant the tomato seedlings deep enough so that the soil hand just beneath its cotyledons .

Most solid food crop seedling with stems can handle having part of their stem buried .

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Be careful not to implant the seedling too deep . forfend start out any grunge on top of the growing stage of the works , from which the plant will continue to farm novel leave of absence . At the attender growing point of the industrial plant , soil can damage the leaves and invite disease .

stride 5 : at once water the seedlings in their new containers . Working with moist or slightly dry soil is easier when pot up . However , this can wilt the plant quickly , especially on sunny days . piddle potted up seedling directly to impregnate the new soil in the great deal . This will relieve stress for the newly transplanted seedling .

Keep Learning !

Three 3-inch pots filled with soil behind a tray containing many small tomato seedlings

Fill the new pots with soil and create a hole large enough to fit the plant.

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Two hands teasing apart one small tomato seedlings from two others

Gently tease apart the seedlings.

A tray of 3-inch pots, each with a hole and a small tomato plant in the center.

Gently place each plant in its own pot.

A full tray of 3" pots, each with one tomato plant.

Lightly pack the soil around the plant to ensure good root-to-soil contact.

A three inch pot with a tomato seedling. The tomato seedling has much of its stem above the soil line.

This tomato seedling is not planted deep enough.

A three-inch pot with a small tomato seedling. The seedling’s stem is buried to just beneath its first set of leaves.

Plant tomato seedlings deep enough that the soil reaches just below its cotyledons.