Manzhosmathe green windowsill: a houseplant reference

An independent reference about houseplants. It is not a shop or a veterinary clinic and is not connected with the former website on this domain. If a pet or a child has eaten part of a plant, contact a vet or a doctor.

Guides

Practical guides

The first guide in this section is about repotting, a job beginners often fear and so put off for years or, on the contrary, take on far too often. A plant needs repotting when its roots are cramped and the potting mix no longer soaks up water or lets air through. Below is a calm sequence of steps that suits most ordinary houseplants in pots.

Repotting is a house move. It is easier for a plant when the new home is only a little bigger than the old one and nobody rushes it to settle in.

— Margin note

What to prepare

  • A new pot slightly wider than the old one, always with a drainage hole in the bottom.
  • Fresh potting mix that suits your species: some plants need a loose, light mix, others a denser one.
  • A thin drainage layer for the bottom, if your species needs one.
  • Gloves, especially if the plant has irritating sap, as dieffenbachia does.
  • Plastic sheeting or newspaper for the table and clean scissors for trimming damaged roots.
  • A notebook or notes on your phone to record the repotting date.

  1. Make sure repotting is really needed

    Signs that a plant is cramped include roots poking out of the drainage hole or wound tightly around the whole root ball, and water that runs straight into the saucer without soaking into the soil. If you see none of this, the plant can stay in its old pot for a while longer.

    Hypothetical example: a plant owner sees white root tips under the bottom of the pot and realises the plant is ready for a new home.

  2. Pick a good time

    Many plants cope with repotting more easily during active growth, when they have the energy to grow new roots. It is better not to disturb a plant that is flowering or weakened unless there is an urgent reason, such as rotting soil.

    Hypothetical example: a beginner postpones repotting a flowering African violet until it has finished blooming.

  3. Prepare the new pot

    Check that there is a hole in the bottom for water to drain. The new pot should not be much bigger than the old one: in an oversized container the potting mix stays wet for a long time and the roots risk rotting.

    Hypothetical example: instead of a huge planter to grow into, the owner picks a pot only slightly wider than the old one and waits patiently for next time.

  4. Take the plant out carefully

    Moisten the soil lightly the day before so the root ball comes out more easily. Turn the pot over, supporting the plant at the base of its stems, and tap the rim. Do not pull hard on the stem: that is an easy way to tear the roots.

    Hypothetical example: the sides of a plastic pot are gently squeezed by hand, and the root ball slides out in one piece.

  5. Inspect the roots

    Healthy roots are usually firm and pale. Dark, soft patches with an unpleasant smell point to rot and are best removed with clean scissors. A tight tangle can be teased apart gently with your fingers.

    Hypothetical example: a few dark, soft tips turn up on the roots of a ficus, and the owner realises they had been watering too generously.

  6. Plant at the same depth

    Put a little fresh potting mix in the bottom, set the plant in place and fill in around the sides, firming it lightly. The base of the stems should sit at the same height as before, not deeper.

    Hypothetical example: to avoid burying the stem, the owner marks the old soil level on it while the plant is still in its old pot.

  7. Water moderately and let it rest

    After repotting, water the plant just enough for the potting mix to settle, then empty the saucer. Put the pot back in its usual place, away from harsh sun. Do not feed it for a while: the roots need to establish first.

    Hypothetical example: after repotting, a spider plant moves from a bright windowsill a little further into the room for a while, then returns to its spot.

  8. Make a note and keep watch

    Write down the repotting date and the type of potting mix. In the first weeks, keep an eye on the leaves: slight drooping can be a normal reaction, but wilting that drags on while the soil is damp is a reason to check the roots.

    Hypothetical example: the owner’s notebook shows that after the last repotting the plant recovered faster, so they follow the same steps again.

Common mistakes

  • Repotting into a pot without a drainage hole: water stagnates and the roots rot.
  • Choosing a pot much bigger than the old one in the hope that the plant will grow faster.
  • Feeding the plant generously straight after repotting.
  • Burying the stem below its previous soil level.
  • Repotting every new plant on its very first day, before it has had a chance to get used to your home.
  • Putting a freshly repotted plant in direct sun or next to a hot radiator.

If something does not fit

  • If the plant is too big to repot, you can carefully replace just the top layer of potting mix.
  • If you do not have the right pot yet, it is better to wait than to plant into a container with no drainage hole.
  • If you are not sure which potting mix is right, check the description of your species or ask an experienced grower.

Check yourself

  • Repotting is really needed: the roots are cramped or the potting mix has gone bad
  • The new pot is only slightly wider than the old one and has a hole in the bottom
  • The potting mix matches your species’ needs
  • The plant came out without tugging on the stem
  • The roots have been inspected and rotten parts removed
  • The plant sits at the same depth as before
  • The saucer was emptied after watering
  • The repotting date is written down

Catalogue of articles in English

This is where we will gather standalone articles for English-speaking beginners: practical walkthroughs, answers to common questions and explanations of the basic ideas behind houseplant care.

What we are working on

  • Getting through the heating season, when the air near radiators turns dry and plants start to sulk.
  • Choosing plants for a rented flat with small windows, little floor space and a landlord to keep happy.
  • Telling a thirsty plant from an overwatered one when both start to droop.
  • Writing simple care notes for a friend or neighbour who looks after your plants while you are away.
  • Spotting fungus gnats early and keeping them from spreading to the rest of your plants.

How we publish

  • Articles in this catalogue are written separately for each language version and are not translations.
  • Some articles link to third-party websites, including gaming services; we do not control their content, prices or terms.
  • We do not sell plants or care products and do not publish shop rankings, prices or reviews.
  • Questions

    Short answers about watering, light and placement, pests, pets and children.

  • Reference

    A beginner’s glossary: drainage, feeding, cuttings, bright indirect light, root rot and quarantine.

  • Sections

    Four topics: choosing a spot, watering and light, repotting and potting mix, and plant health.

Sources

  • Houseplant care handbooks
  • Veterinary home safety leaflets

Information is current as of the date this page was prepared. Houseplants differ widely in what they need from light, water and potting mix, so check the requirements of your own species before you change how you care for it.