End of summer: how to prepare your plants for coming back indoors and the first chills (step-by-step calendar)

You wake up one late August morning and sense that first subtle hint of coolness in the air signaling the end of summer. Your plants, which have enjoyed sun and warmth on the terrace or in the garden for months, now need special attention. Bringing them indoors is not just a simple move but a true transition protocol that, if managed correctly, will prevent stress and problems. This guide provides a detailed calendar, week by week, from August 20 to September 30, with all the necessary actions to prepare your plants for the seasonal change and the first autumn chills. Following these steps will ensure a smooth transition and optimal health for the months ahead.

Table of Contents:

• Operational calendar: what to do week by week (August 20 – September 30)
• The 4 most sensitive houseplants to re-entry stress (and how to manage them)
• The 4 terrace plants that require specific end-of-summer care
• Stress from being brought back inside: 5 signs to recognize immediately
• Late summer repotting: who should do it and who shouldn't
• What NOT to do at the end of summer (mistakes you would pay for in October)
• The practical kit for the late summer transition

Operational calendar: what to do week by week (August 20 – September 30)

The late summer transition for plants lasts about 6 weeks, from August 20 to September 30. Reduce fertilization, inspect for pests, gradually acclimate to less light, and bring indoors only when the heating is still off to avoid thermal shock. This schedule will guide you step by step, ensuring optimal preparation.

At this time, the key word is gradualness. Imagine your plants as travelers preparing for a long winter: they need time to adapt. Every week counts to mitigate re-entry stress and ensure your late summer plants face the seasonal change in the best way. A good starting point is to review your July green calendar to understand where your plants are coming from.

For plants that have spent the summer outdoors, the transition from the external environment, with its abundance of light and ventilation, to the indoor environment, which is more static and less bright, can be traumatic. Our growers recommend closely observing each specimen. Reducing fertilization is crucial: nutrient supply should decrease as the plant slows its metabolism. If you continue fertilizing at the same summer frequency and dose, you might encourage weak and vulnerable growth.

Inspecting for pests is a step that should never be overlooked. Scale insects, spider mites, or aphids can hide under leaves or in stem crevices. A thorough cleaning with a damp cloth and, if necessary, the application of a natural insecticide will save you from future infestations at home. Remember, plants that have endured the summer heat, like those mentioned in our article on heat-resistant plants for August, may have accumulated more stress and therefore require even more careful inspection.

The transition area, such as an unheated veranda or covered balcony, offers an ideal intermediate environment. Here, plants can acclimate to less extreme light and temperature conditions compared to the heated interior of the home. This 1-2 week step is essential for the most delicate species. Only when nighttime temperatures consistently approach 10-12°C, and home heating is not yet on, is it time to bring them inside permanently. This is also the right time to think about how you will arrange your plants for your home office.

The 4 most sensitive houseplants to re-entry stress (and how to manage them)

Some houseplants react more strongly to re-entry stress, showing symptoms like yellowing or drooping leaves due to temperature and light changes. Handling them carefully is crucial for their health.

Calathea Sanderiana

Symptom: Leaves curl or show dry tips and burnt edges. Calathea is notoriously sensitive to humidity fluctuations and drafts.

Preventive action: Place it in a transition area with indirect light and high humidity (60-70%). Mist the leaves daily with distilled or rainwater. Consider using a humidifier or a saucer with moist expanded clay.

Timing: Begin gradual relocation as early as late August, with final return indoors within the first two weeks of September.

Monstera Deliciosa

Symptom: Large leaves may yellow, especially older ones, or show brown spots. This often indicates water or light shock.

Preventive action: Gradually reduce watering, allowing the top 5 cm of soil to dry out between waterings. Ensure it receives plenty of bright indirect light, but not direct. Avoid repotting unless strictly necessary to prevent additional stress.

Timing: Start reducing direct sun exposure in early September, with final return indoors by mid-September.

Hoya Kerrii Variegata

Symptom: Heart-shaped leaves may lose variegation or show dark spots. It is very susceptible to cold and overwatering.

Preventive action: Ensure the temperature does not fall below 15°C. Drastically reduce watering, watering only when the soil is completely dry. Provide bright but indirect light to maintain variegation.

Timing: Bring this plant indoors between late August and early September, before nighttime temperatures drop too low.

Philodendron Birkin

Symptom: New leaves may grow small or deformed, and existing ones may lose their characteristic light variegation, becoming greener. It is sensitive to humidity and light fluctuations.

Preventive action: Maintain constant humidity around 50-60%. Place it in a spot with plenty of indirect light. Avoid cold drafts. Check drainage to prevent waterlogging.

Timing: Move the Philodendron Birkin to a protected area in early September, returning it indoors by the third week of the month.

These plants, with their unique beauty, require special attention during the transition period. A little extra effort at the end of summer will reward you with lush, healthy plants throughout the winter. Our growers have noticed that daily observation can make a difference in catching the first signs of distress.

Discover our plants

The 4 terrace plants that require specific end-of-summer care

Terrace plants, accustomed to full sun and ventilation, require targeted care at the end of summer to prepare for returning indoors or wintering outdoors, especially Mediterranean species.

Oleander (Nerium oleander)

What to do: Gradually reduce watering starting from mid-September, especially if potted. Perform light pruning to remove wilted flowers and shape the plant, but avoid drastic pruning that would stimulate weak new growth. Protect the roots in pots with mulch or move it to a sheltered area if temperatures drop below 5°C.

What NOT to do: Do not fertilize after late August. Do not prune severely in September, as the plant needs to focus energy on preparing for winter dormancy. Avoid waterlogging in the saucer.

Dipladenia (Mandevilla spp.)

 

What to do: Reduce watering as temperatures drop. Dipladenia is sensitive to cold, so be ready to move it to a protected place (e.g., cold greenhouse, bright stairwell) when nighttime lows approach 10°C. You can perform light pruning to shape it before bringing it indoors.

What NOT to do: Do not leave it outside if temperatures drop below 5°C, as it will suffer irreversible damage. Avoid overwatering during dormancy to prevent root rot.

Callistemon Red Rocket

What to do: This plant is more cold-resistant than the previous ones, but if potted and in areas with harsh winters (below -5°C), it is advisable to protect it. You can wrap the pot with insulating material or move it against a sheltered wall. Reduce watering in autumn.

What NOT to do: Don’t worry about some yellowing leaves; this is normal as the plant prepares for winter. Avoid drastic pruning in late summer; wait until spring for more vigorous maintenance pruning.

Eucalyptus Gunnii

What to do: The Eucalyptus Gunnii is a sturdy plant and tolerates cold well, even down to -15°C if well rooted in the ground. If potted, ensure excellent drainage and that the pot is appropriately sized. Reduce autumn watering. It does not need shelter unless the winter is exceptionally harsh.

What NOT to do: Do not fertilize in late summer, as growth naturally slows down. Do not fear the first cold spells; this plant is accustomed to harsher climates. If the leaves turn reddish, it is a normal reaction to the cold, not a sign of stress.

Each species has its specific needs, but the common thread is always observation and gradualness. With the right care, late summer plants will continue to enhance your spaces for many years.

Stress from being brought back inside: 5 signs to recognize immediately

Plants communicate their discomfort through clear visual signals. Recognizing these signs of stress from being brought back inside early is essential to intervene promptly and save the plant from further damage.

1. New yellow leaves: If younger leaves turn yellow, it may indicate overwatering or lack of light, both common when moving from outdoors to indoors.
2. Dry leaf tips and edges: This is often a sign of low ambient humidity, typical of heated indoor environments.
3. Drooping or limp leaves: Can be due to thermal shock, excess or lack of water, or simply an adaptation to lower light intensity.
4. Brown or dark spots on leaves: Often indicate sunburn (if the plant was exposed too quickly to direct sunlight after being brought back inside) or, conversely, root rot from overwatering.
5. Small white dots or fine webs: These are clear indicators of pests like scale insects or spider mites, which take advantage of the plant's stress to multiply.

How can you tell if a plant is stressed from being brought back inside? Careful observation is key. Any change in color, texture, or leaf drop can be a warning sign. Never underestimate these signals, because early intervention can make a difference. For example, a Calathea Sanderiana with curled leaves is a clear sign of low humidity, while a Monstera Deliciosa with yellow, limp leaves might be suffering from overwatering.

Late summer repotting: who should do it and who shouldn't

Can plants be repotted in September? The answer is yes, but with caution. Late summer repotting is a delicate operation that should only be done if strictly necessary, to avoid further stressing the plant before winter.

Yes to repotting if:

• Roots are coming out of the pot's drainage holes.
• The plant has stopped growing and the substrate is completely depleted.
• The soil is compacted and no longer absorbs water properly.
• You have purchased a new plant and the pot is clearly too small for its size.

In these cases, repotting should take place between late August and the third week of September, to give the plant time to settle before the vegetative slowdown. Use a pot only one size larger and a high-quality soil mix specific to your plant's needs.

No repotting if:

• The plant is visibly stressed or sick.
• There are no obvious signs of root distress.
• The plant is in full bloom or about to bloom.
• You don't have time to dedicate to the operation with the necessary calm and attention.

In these scenarios, it is better to postpone repotting until the following spring, when the plant will resume its vegetative cycle with more energy. Unnecessary or poorly done repotting can cause even greater shock, compromising the plant’s health throughout the winter.

Our lab suggestion: For effective repotting, always choose a quality substrate. Our nurserymen recommend a well-draining universal potting soil, enriched with perlite or pumice. If the plant requires it, like orchids or acid-loving plants, opt for a specific substrate. This is the ideal time to explore our TerraFlora soil collection, formulated to ensure maximum root well-being.

What NOT to do at the end of summer (mistakes you would pay for in October)

Avoiding some common mistakes at the end of summer is as important as following the right practices. These errors can compromise the health of your plants and cause problems that will strongly manifest in October.

• Do not bring plants indoors too early: Waiting for nighttime temperatures to consistently drop below 10-12°C, and for the heating in the house to still be off, is crucial. Bringing them in earlier means exposing them to an environment that is too warm and dry, causing shock.
• Do not fertilize with summer doses: Plants are slowing down their metabolism. Continuing to provide excess nutrients stimulates weak growth and makes them more vulnerable to diseases and pests.
• Do not neglect pest inspection: Skipping this step means bringing scale insects, red spider mites, or other insects into the house, which will multiply quickly in protected indoor environments.
• Do not repot unless necessary: Repotting is stressful. If the plant does not urgently require it, postpone the operation until spring.
• Do not overwater: With the drop in temperatures and reduced light, plants consume less water. Excess water is the main cause of root rot in autumn.
• Do not place immediately near heat sources: Once brought indoors, plants should not be placed immediately near radiators or stoves. Dry and hot air is a strong stress.

These mistakes, although common, can have significant consequences. Our nurserymen have seen many plants suffer due to a rushed return indoors or improper watering management. Remember, patience and observation are your best allies during this transition period. Which plants fear the most the temperature swings at the end of summer? Generally tropical ones, like Calathea and Ficus, which need humidity and stable temperatures.

The practical kit for the late summer transition

To best handle bringing your plants indoors, having the right tools at hand makes all the difference. It’s not just about products, but true allies for the well-being of your green friends.

First of all, the potting soil. If you have decided to repot some plants, a quality substrate is essential. The TerraFlora line offers specific mixes for every need, ensuring proper drainage and nutrient supply. Good potting soil is the foundation for a healthy and stress-resistant plant.

For cleaning and light pruning, ToolsFlora tools are indispensable. Sharp and disinfected scissors prevent diseases and allow clean cuts. A soft cloth and a spray bottle for distilled water will help keep leaves clean and maintain necessary humidity.

Transition watering requires precision. AcquaFlora watering cans, with their ergonomic design and thin spouts, allow you to dose water gently, avoiding excess that could cause root rot. Remember that plants at the end of summer need less water than in the warmer months.

Finally, don’t forget accessories for environmental well-being. Large saucers with a layer of expanded clay will maintain constant humidity around the plant. The ceramics from Officine dei Giardini di Giulia, besides being aesthetically pleasing, offer pots with excellent drainage, essential for root health. For a touch of design and functionality, also consider items like the Rectangular Frame of Stabilized Moss and Lichens or the Mini Frame in Stabilized Moss and Lichens 14.5x24.5 cm – Black Frame. | Made in Italy, adding greenery without maintenance.

Common question from our customers: Many ask if it is necessary to buy new pots. The answer is: only if the current pot is too small or damaged. Otherwise, a good cleaning and drainage check are sufficient. Our handcrafted ceramics, like those from Le Officine dei Giardini di Giulia, are designed to last and provide the best environment for your plants.

Frequently Asked Questions

When should plants be brought indoors from the balcony?

The final return of plants indoors from the balcony should take place between late September and early October, when nighttime temperatures consistently drop below 10-12°C. It is essential that the home heating is still off to avoid thermal shock. Plan a 2-3 week transition phase in an intermediate environment, such as a veranda or covered balcony, to gradually acclimate them.

What should you do to houseplants before bringing them back indoors?

Before returning indoors, it is essential to gradually reduce fertilization starting from the end of August and carefully inspect plants for pests. Clean the leaves with a damp cloth and, if necessary, treat with natural products. Move the plants to a transition area with indirect light to help them adjust to the new environment, reducing stress from the move.

Which plants are most sensitive to late summer temperature fluctuations?

Tropical plants are the most sensitive to late summer temperature fluctuations. Species like Calathea, Monstera, Hoya, Philodendron, and Ficus react with yellowing, drooping, or curling leaves. They need an environment with constant humidity and stable temperatures. A gradual return and careful watering management are crucial for these delicate late-summer plants.

Can plants be repotted in September?

Yes, plants can be repotted in September, but only if strictly necessary and preferably by the third week of the month. This period allows the plant to settle into the new substrate before winter dormancy begins. Avoid repotting if the plant is stressed or flowering, and postpone the operation to the following spring to minimize the risk of shock.

Why do my plants have yellow leaves at the end of August?

Yellow leaves at the end of August can indicate various stress factors related to the transition. It could be overwatering due to temperature drops, lack of light, or shock from temperature fluctuations. Nutrient depletion in the soil or the presence of pests can also cause this symptom. Careful observation and targeted intervention are essential.

When should you stop fertilizing plants at the end of summer?

You should start reducing plant fertilization from the end of August, cutting doses by 50% during the first week and then completely stopping fertilizer application by the end of September. This prepares the plant for the slowdown of its growth cycle and winter dormancy. You will resume fertilizing in spring.

We hope this detailed calendar helps you manage your plants effectively at the end of summer. Save or print this guide to always have it handy. Remember, the well-being of your plants depends on your attention and your ability to anticipate their needs. Explore our selection of TerraFlora soils and ToolsFlora tools to have everything you need. Our young team of nurserymen is always available to offer advice and support. We look forward to seeing you at I Giardini di Giulia to discover the best of greenery.