The reasons why we do repotting :

• Root bound - as the plant develops, the roots occupy more and more of the available space in the pot. In the short term, the plant is not significantly affected (some plants may even have better vegetative growth when they are root bound), but in the long term, there may be some problems: the plant may slow down or stop its growth, the substrate may it no longer retains enough water and nutrients (therefore, more frequent watering and fertilization is necessary). The phenomenon can have multiple causes - sometimes the plants come in undersized pots for better transport efficiency, sometimes they simply have a very fast growth rate and require more frequent moving to new culture pots. However, there are plants that do very well and have a spectacular vegetative development when they are at a certain level of root bound - some examples: hoya, some orchids (epiphytes), Spathiphyllum, most ficuses, most succulents and cacti, ferns, philodendron and epipremnum, etc.

The root bound condition does not require an immediate change of the pot - if the plants look good and have a proper vegetative development, replanting can be postponed until we reach the right season (growing season). There are several levels of root bound, and seriously affected plants show clear signs when urgent replanting is necessary: ​​dehydration, wilting, falling leaves, etc.

• Unsuitable substrate - each producer uses its own formula for the substrate, adapted according to several factors: growing system, watering system, general conditions in the greenhouse, growth performance, etc.. In some situations, the substrate can be considered unproductive for the microclimate in our homes or incompatible with our watering habits. In this situation, we will make an assessment and determine if it is necessary and how urgent a possible replacement of the substrate is.
• Root rot - the plant has rotten roots and starts to deteriorate. The causes can be multiple, and this scenario is encouraged by watering habits inappropriate to the species and/or microclimate and/or a substrate inappropriate to the microclimate or growing style. Sometimes, plants can reach this stage, following long international transports and temperature differences in the distribution/logistics chain, or they can reach this stage when we try to accommodate (adapt) the plants in a new environment, significantly different from the one in which the plant was grown. It is not a reason to panic, but if the plant is significantly affected, it is necessary to change the substrate, disinfect or change the pot and remove the damaged roots as soon as possible.

Replanting, depending on the seasons

• spring - is the best option. The day gets longer, the temperatures rise naturally and the plants start growing again. This season is the most favorable for the rapid development of a healthy root system.
• summer - replanting will be done with increased attention to watering (more frequent watering), without further exposure to the sun. The plants will be kept in cool spaces , so as to avoid additional stress caused by high temperatures.
• autumn - repotting can only be done for certain types of plants , when the day is still long enough and we know the species well enough to anticipate the subsequent evolution.
• in winter - only replantings considered urgent or minimally invasive will be done . For the success of replanting this season, it is necessary to place the newly moved plants in a space as bright as possible, properly heated. The ideal temperatures for the development of the root system: 20-22 degrees. Above 23 degrees, the development of pathogens is favored, which can irreparably damage a sensitive plant (freshly moved). Avoid placing newly moved plants near a "cool" window - the temperature near the window can be up to 4-5 degrees lower (than that in the rest of the room). Avoid placing newly moved plants near heat sources (radiator, heated floor, etc.).

How do we determine if replanting is necessary?

Evaluation of the plant . If we find that the plant looks bad - signs of weakness, unusual colors, dehydration, atypical growth, etc. - we will proceed to extract the plant from the pot. Usually it is enough to gently press the pot all around to pull the plant out, keeping the whole "bale" of substrate. In advanced root bound stages, it is necessary to cut the pot to extract the plant (we should make sure that we have pots of similar size before this operation).

Evaluation of roots . After extracting the plant from the pot, the roots will be visible. If we notice only a few damaged roots, we will try to remove them without disturbing the plant too much. If the roots are very affected (over 50%), it is necessary to remove them, replace the substrate and replant. The presence of degraded roots is normal and natural for most plants, both in nature and under culture conditions.

Evaluation of the substrate . After extraction from the pot, the evaluation of the substrate becomes easy. We will observe what materials the substrate is made of (we will think about the composition, related to our watering habits and microclimate) , if it is decomposed and if there are fungi/molds (but also in what proportion). Most of the mushrooms and molds in pots are harmless to plants (they are not pathogenic), but their massive presence indicates a degraded substrate, possibly too acidic (due to decomposition) for sensitive plants. A degraded and acidic substrate can be a good host for specific pathogens (soil borne diseases) - root rot, sclerotium, fusarium (extremely rare), phytium, rhizoctonia, etc.

How do we replant?

Choosing the pot . For a healthy plant, the new pot will have a diameter of only 2-3 cm larger. For an affected plant, where it was necessary to remove a substantial part of the root system, we will use a similar or smaller pot, capable of supporting the plant.

Selection of pots available at Secret Garden (link).

In the case of plants that remain without a root system or with an insignificant number of roots, we will use specific methods of regeneration (e.g. a bed of sphagnum moss , rooting in a bag, etc.). Before cutting from the roots of the plants we will document and make sure that their appearance is not appropriate - usually the damaged roots have a specific color (black or brown) and consistency (soft, juicy or completely dry). We will NOT cut firm roots, regardless of color.

Choosing the substrate . The substrate will be chosen according to the species and its needs , taking into account our watering habits, the time we can allocate to plant care and the microclimate in which we will grow them. As a general rule, it is preferable to use a well-drained substrate, but with a certain water retention, so that watering can be done at a reasonable time interval.

Inorganic substrate and hydroponic culture . It eliminates or limits the risks associated with pathogens, but water and nutrient retention are keywords when we think about choosing a substrate or a culture method. The use of the inorganic substrate (loam/clay balls, perlite, etc.) requires greater maintenance and increased attention to the needs of the plant (special nutrients are used for hydrocultures, adapted for each type of plant), depending on the setup used.

Selection of substrates and raw materials available at Secret Garden (link) .

Replanting with minimal interventions . Each plant is alive and develops a root system whose purpose is to feed and stabilize it in a position that will allow it to absorb the necessary light through the leaves. Moving a plant is a delicate operation that requires a lot of attention, because the roots can be brittle (they can break easily), and the plant can thus be destabilized. If the roots and the existing substrate are in good condition, it is enough to extract the plant from the old pot and replant it in the new pot, supplementing with substrate.

Removal of the old substrate . We place the pot in a container with warm water - after about 10 minutes, the substrate will be soft, moist and easy to remove. If we encounter difficulties (especially in the case of root bound), we can use a water jet with reduced pressure to remove the remains of the substrate between the roots.

Application of fungicides . When replanting, it is recommended to use a broad-spectrum fungicide to prevent the development of pathogens. The application can be done by immersing the pot in the prepared solution (dipping), until the substrate absorbs a sufficient amount.

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