For a long time, the tradition of celebrating Fat Thursday—when we indulge in donuts, angel wings, and other treats—was all about preparing for the upcoming period of fasting. With the progress of civilization, many food-related worries have disappeared for humans, and the influence of the Catholic Lent has also waned. However, fasting is a natural phenomenon in nature. Plants, too, go through dormancy periods, during which they slow down their metabolic activity to survive harsher conditions.
First, we’ll look at their fasting—what they are preparing for—and then at their Fat Thursdays—how and when they do it. Let’s begin!
Types of Plant Dormancy – How Do Plants Experience “Winter Fasting”?
Fasting in plants is better described as dormancy. It is an adaptive mechanism that allows them to endure unfavorable environmental conditions, such as winter frosts or summer droughts. There are two main types of dormancy—deep dormancy and imposed dormancy—but there are also several specific survival strategies that vary depending on the species and climate.
1. Deep Dormancy (Endogenous, True Dormancy)
This occurs in plants that enter a dormant state regardless of external conditions. During this period, even if temperatures suddenly rise, the plant does not resume growth because its internal processes are “locked.”
➡ Examples:
Deciduous trees in temperate climates (e.g., oak, beech, maple)
Bulbous plants (e.g., tulips, daffodils, hyacinths)
Some perennials (e.g., peonies, daylilies)
🔹 How do plants prepare?
They shed their leaves to reduce transpiration and minimize water loss.
They actively store sugars and starch in roots, rhizomes, and bulbs.
They gradually change their cell structure to protect against freezing.
🔹 When does it end?
The plant becomes active again only after specific conditions are met, such as after a cold dormancy period when it has accumulated a required amount of "chill units."
Gladiolus plants in late February and early March are in the middle of their fasting period. They won’t start "eating" again for another two months.
2. Imposed Dormancy (Exogenous, Environmental Dormancy)
This type of dormancy is directly influenced by external conditions. If the temperature and humidity become favorable, the plant can "wake up" even outside its usual growth cycle.
➡ Examples:
Some potted plants (e.g., ficus, dracaena) – they can grow all year but slow down in winter due to lower light availability.
Biennial vegetables (e.g., carrots, beets, parsley) – they grow in the first year but may flower and seed in spring if they survive winter.
Ornamental shrubs (e.g., hydrangeas, rhododendrons) – if winter is mild, they may start growing prematurely.
🔹 How do plants react?
They slow down growth in response to cold, drought, or lack of light.
Some retain their leaves (e.g., evergreen plants).
In favorable conditions, they can resume growth without needing a full dormancy cycle.
🔹 Can it be shortened?
Yes! We can stimulate plants to grow earlier by:
✅ Providing optimal temperature and humidity (e.g., moving bulbs to a warmer place).
✅ Using artificial lighting in greenhouse cultivation.
✅ Accelerating germination through stratification (e.g., storing seeds in the fridge).
Other Survival Strategies – Special Forms of Plant “Fasting”
Besides classical dormancy, plants use different strategies to endure tough conditions:
🌨 Hibernation – Adapting to Extreme Cold
Some species survive freezing temperatures by producing antifreeze-like compounds in their cells, such as sugars and amino acids.
➡ Examples:
Conifers (e.g., pine, spruce) – their needles have a waxy coating, and the inside of the needle is frost-resistant.
Lavender and rosemary – they partially lignify, which helps limit water loss.
🔥 Estivation – Summer Dormancy (Dry Fasting)
Some plants enter dormancy not in winter but in summer to survive extreme drought and high temperatures.
➡ Examples:
Mediterranean bulbous flowers (e.g., cyclamen, freesia) – they dry up their leaves and bulbs in summer, then restart their cycle in autumn.
Cacti and succulents – during extreme heat, they close their stomata and enter minimal activity mode.
What Does This Mean for Gardeners?
Understanding dormancy types helps in plant care:
✔ Avoid fertilizing plants in deep dormancy—they won’t absorb nutrients.
✔ Reduce watering for dormant potted plants in winter.
✔ Protect bulbs and perennials from premature awakening, e.g., by shielding them from sudden thaws.
Plants’ Fat Thursday – How Do They Stock Up Before Fasting?
Plants also have their version of Fat Thursday, and bad news for those who love moderation—they often don’t limit it to just one day! Their preparation for fasting involves mobilizing energy reserves for tougher conditions like winter, drought, or other dormant periods. Depending on the species, this process takes different forms.
Plants’ Strategies for Survival
Plants store sugars, starch, fats, and proteins in their storage organs (roots, bulbs, rhizomes, seeds) to survive dormancy. This is their equivalent of us feasting on donuts before fasting! 🍩🌱
Physiological Maturation – The Plant Pantry
This is when plants shift their metabolism to intensely store nutrients, usually at the end of the growing season, in summer or autumn.
📌 Examples:
🌳 Deciduous trees (e.g., oaks, maples) – store starch in roots and trunk before winter.
🌷 Bulbous plants (e.g., tulips, lilies) – their leaves photosynthesize, transferring sugars to the bulbs.
🍇 Grapevines – in autumn, sugars concentrate in stems and roots.
Tulips at the turn of February and March are still before their Fat Thursday, which will come after blooming.
Leaf Senescence – The Last Chance to Recover Nutrients
This process allows plants to retrieve valuable nutrients from leaves before shedding them, just like we stockpile food before winter.
📌 Examples:
🍂 Deciduous trees – before dropping leaves, they transport nitrogen, phosphorus, and sugars to branches and roots.
🌿 Perennials (e.g., hostas, peonies) – their leaves turn yellow while nutrients move to rhizomes, helping them survive winter.
🍁 Grapevines and fruit shrubs – senescence not only helps them endure winter but also influences next year’s fruit yield.
Hardening – The Plant Way to Survive Frost
This is the process by which plants prepare for winter chills. They accumulate simple sugars, which act as a natural "antifreeze" and protect them from freezing. Additionally, some plants alter the structure of their cell membranes to better withstand extreme temperatures.
📌 Examples:
🌲 Coniferous plants – increase their sugar content and modify their cell membrane composition to endure frost better. Their needles are covered with a thick cuticle layer, further reducing water loss.
🌾 Ornamental grasses – change their cell biochemistry, allowing them to survive low temperatures. Some species can even partially dry out to reduce the risk of damage caused by water freezing in tissues.
Filling Seeds – Energy for the Future
For annual plants, "Fat Thursday" is the moment when all their energy is redirected into seeds, which serve as a reserve for the next season. This is a strategic survival moment, as plants invest everything in the next generation.
📌 Examples:
🌾 Grains (wheat, corn) – at the end of the season, assimilates are transferred to kernels, forming starch-rich grains that can survive in the soil for a long time.
🥜 Legumes (peas, beans) – proteins and starch concentrate in the seeds, giving them the strength to germinate the following year.
🌻 Sunflowers – intensively accumulate fats in their seeds, making them a valuable energy source for both the plant and the animals that feed on them.
Thanks to this mechanism, plants not only secure their offspring but also contribute to ecosystem balance—seeds serve as food for birds, insects, and mammals, which help disperse them. 🌱
When Do Plants Have Their "Fat Thursday"?
📆 Seasonal plants (annuals) – intense nutrient storage before the end of their life cycle, e.g., summer-autumn.
📆 Perennials – start stockpiling in autumn or before a drought period.
📆 Bulbous plants – after flowering, they redirect energy to their bulbs.
Every plant has its survival strategies—observing them can teach us valuable gardening lessons! 🌱
Do plants also see their food this way just before the fasting period begins?
Summary – Plants’ Binge Before Fasting!
🌱 Plants don’t eat donuts, but they do something very similar—they store energy intensively before tough times. Now that you know their strategies, you see what gluttons they are! Plants do everything they can to feast when possible because they know hard times are ahead. 🍩🌿
In the past, fasting was a natural part of human life, giving our bodies a break from overeating. Science now suggests various ways to reintroduce intermittent fasting. Maybe it’s worth following plants’ example and bringing back this tradition?
But before that… let’s bake and eat some donuts! 🍩 Have you baked yours yet, or are you just getting started? How many can you eat? Share in the comments! 😃