When Is the Best Time to Plant in Ireland?
Peter Dowdall · Garden Timing · Ireland
The best time to plant in Ireland is autumn into winter
Container grown plants can be planted twelve months of the year, and once that became true most of us stopped thinking about timing at all. I think our changing climate has made the old planting season worth returning to.
My own preference for planting a garden is September to February, avoiding any spell when the ground is saturated or frozen. The traditional advice was to plant during the months with an R in them, there was sound horticultural reasoning behind that, and I now believe it is close to right again with one adjustment. This page sets out what the planting windows actually are in Irish conditions, what changes if you plant in spring instead, and what to get right in the soil before anything goes into the ground.
Planning ahead
What you plant has to be decided before when you plant it.
If you are planning a new border, a full replant or a garden from scratch, the plan needs to be settled before the planting window opens. Planting by Numbers takes a garden from the first conversation to a bespoke planting plan to plants delivered to your door, labelled and ready to go in.
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Peter Dowdall, Irish horticulturist and broadcaster, explains why autumn is still the strongest planting window in Ireland, how the container growing and bare root seasons differ, and what to do if you are reading this in spring with plants already bought.
The Short Answer
The best planting months for Irish gardens
Container grown plants can be planted twelve months of the year in Ireland. My own preference for planting a garden is September to February, avoiding any period when the ground is saturated or frozen. Bare root stock sits alongside that, from November through to February or March.
So this is a recommendation, not a restriction. Almost everything sold in a pot will go into Irish soil in any month you choose, provided the ground is workable on the day. What changes from month to month is not whether the plant survives being put in. It is how much root system it has built by the time it meets its first real test, and in Irish gardens that test now arrives in summer.
Planting between September and February works for three reasons that all point the same way.
- The soil holds warmth well into autumn, so roots continue growing and establishing long after the top growth has gone quiet
- Rainfall is usually reliable, so the plant is not depending on you with a watering can through its most vulnerable weeks
- The plant gets the rest of the autumn, the winter and the whole spring in the ground before it meets its first summer, which is the season that now does the damage
"Our forefathers were working with the seasons rather than with the retail calendar. A generation or two later, I think they had it right."
The Old Rule
Months with an R, and why the rule existed
You may have heard the expression that you should only plant during the months with an R in them. That is September through to April, and it was not superstition. It was a practical instruction about how plants used to be grown and sold.
In those days, nurseries grew everything in the field. Trees, shrubs and hedging were raised in open ground and then lifted out of that ground to be sold. The only time it is safe to lift a plant out of the soil is when it is dormant, when the top growth has stopped and the plant is not making demands on a root system you are about to disturb. In Ireland, that dormant period broadly matched the months with an R in them.
So the rule was never really about your garden. It was about the nursery. It described the only window in which a plant could be safely taken out of one piece of ground and put into another.
Why the rule fell away
Then modern garden centres arrived, and with them container growing. Nearly all plants sold today are grown in pots and containers, which means nothing has to be lifted out of the ground at all. The root system travels with the plant, intact, in its own compost. Like any other consumer product, plants became available fifty two weeks of the year, and the whole idea of a planting season disappeared from most people's thinking.
That was not wrong, and I want to be clear about it. A container grown plant can be planted twelve months of the year in Ireland, provided the ground is workable on the day. There is no month in which it cannot be done. The separate question of whether the ground is workable at a given moment is one I have covered in detail on is it too early to plant in Ireland. What has changed since the garden centres arrived is not what the plant can tolerate on the day it goes in. It is what it has to survive in the twelve months afterwards.
What Has Changed
Why I have gone back to autumn planting
Over the last few years I have noticed a pattern in Irish gardens that has changed my advice. The extremes at both ends of the year have got sharper, and it is newly planted gardens that pay for it.
We are seeing increased periods of drought and high temperatures through the summer. New gardens struggle badly in those spells, and plants that went in only weeks earlier come under real stress before they have any root system to draw on. At the other end, we are getting periods of excessive rain during the winter months, sometimes in December, sometimes in January, sometimes in February. And we may still suffer extreme low temperatures on top of that.
A plant put in the ground in April has perhaps a month, often less, to establish before the first dry spell arrives. A plant put in the ground in October has the whole winter and the whole spring. That difference is not marginal. In my experience it is frequently the difference between a plant that copes and a plant that does not.
The longer a plant is in the ground and establishing before next summer, the better it will handle heat and dry weather. Roots that have had eight months to spread into surrounding soil are drawing on a far larger reservoir than roots still sitting in the shape of the pot they arrived in.
Plants also establish better if they are in the ground before the heavy rain arrives rather than during it. I would never plant, or work the soil at all, during periods of excessive rain when the ground is flooded or saturated. Getting the planting done beforehand avoids the problem entirely.
The same applies to hard frost. Frozen ground should not be worked or planted into. In most Irish winters there are plenty of workable days between the wet spells and the cold ones, and a window that runs from September through to February gives you enough of them to pick your moment rather than wait on the weather.
This is where I depart from the old rule. I would stop at February. You can still plant in March and April, and plenty of people do, but you will have to be considerably more diligent about watering through the season ahead, because the plant has had far less time to develop a root system before the dry weather arrives.
Getting This Straight
The two planting windows, and why they are not the same thing
A great deal of confusion about planting dates in Ireland comes from two different windows being quoted as if they were one. They are not, and they apply to two different kinds of plant.
Container grown plants
Any month, but ideally September to February
Anything sold in a pot, which today is most trees, shrubs, hedging plants, perennials and grasses, can be planted twelve months of the year. There is no closed season. September to February is simply my preference for planting a garden, because that is when the plant gets the longest run at establishing before it is asked to do anything difficult.
Soil that still holds warmth, reliable rainfall and a long run-in before the following summer are what make it the strongest period of the year to plant. The only days to avoid within it are those when the ground is saturated or frozen.
Bare root plants
November to March
Bare root stock is still grown in open ground and lifted while dormant, exactly as the old rule described. It is supplied without a pot and without compost around the roots, and it is only available during those months. Outside that window it does not exist to buy, and planting it once the plant has broken into growth causes real stress.
It is usually considerably cheaper than the potted equivalent, which matters a great deal when you are planting a hedge or a large number of trees.
Where the two windows overlap
November through to February sits inside both windows, and that is not a coincidence. For most Irish gardens that stretch is the single strongest planting period of the whole year. Bare root stock has come available, the rainfall is doing the watering for you, and the plant has the longest possible run before it faces any real stress. Within it, you are simply picking days when the ground is neither saturated nor frozen, and in a normal Irish winter there are plenty of those.
If you are planting a hedge, that overlap is particularly worth working to. I have covered hedge planting and the timing that goes with it in more detail on hedge advice Ireland.
Bulbs sit on a separate schedule again. Spring flowering bulbs go in during autumn and into early winter, and there is a common mistake in planting them too early in the season. I have set out the detail on when to plant spring bulbs in Ireland, and snowdrops are a case of their own, best moved in the green rather than as dry bulbs, which I have covered on when to plant snowdrops in Ireland.
Before the window opens
Knowing when to plant is only useful if you know what to plant
Autumn arrives quickly. If you want a border, a screen or a whole garden planted this September, the decisions about what goes where need to be made over the summer, not in the garden centre car park in October.
A planting plan settles those decisions properly, built around your soil, your aspect and Irish growing conditions. Then the planting itself becomes straightforward.
What is a planting plan?If You Are Reading This In April
What if it is already spring?
Nothing on this page is an argument against planting in spring or summer. It is entirely possible, people do it successfully every year, and if you have plants sitting in pots by the back door then getting them into the ground is very often better than leaving them there.
The difference is one of root systems, and it is worth understanding rather than just accepting. A shrub planted in October has four or five months of root development behind it by the time March arrives. The same shrub planted in March or April has almost none, and it goes into the summer relying on a root ball that is still more or less the shape of the pot it came in.
That does not mean it will fail. It means the responsibility shifts to you. If you plant in March or April you will have to be considerably more diligent about watering through the season ahead than if you had planted between September and January, because the plant simply has not had the time to prepare itself. In autumn the season does that work for you. In spring, you are the one holding the hose, and it needs to be a proper soaking that reaches down and draws the roots after it rather than a splash every evening, which only encourages shallow surface rooting.
Four things that make spring and summer planting work
A newly planted tree or shrub going into a warm spring needs consistent, deep watering through its whole first summer, not just for the fortnight after planting. If you are away, or if you know you will not keep it up, that is a genuine reason to wait until September rather than a small detail.
Water butts and rainwater collection are worth setting up before you plant rather than after. Rainwater is better for plants than treated mains water, it costs nothing, and if a hosepipe restriction comes in during a dry summer, a full butt is the difference between keeping new planting alive and watching it go backwards.
This is the one that matters most, and it is the one most people skip. Soil with good structure holds water when the plant needs it and lets it drain away when there is too much. That single property is what allows a plant to cope with drought, with flooding and with cold. Improving structure is worth more to a spring planted shrub than any amount of feeding. There is more on this on how to improve soil before planting.
Once the plant is in and the ground has been watered, mulch it. Three to four inches, and not less, because a thin scatter of mulch does very little. At that depth it does two jobs at once. It slows the loss of water from the surface by evaporation, so the moisture you put on stays in the root zone rather than going into the air on the first warm afternoon. And it stops weed seeds germinating, which matters more than people expect, because a covering of weeds takes the rain first and a new plant is left with whatever is left over.
What I would hold until autumn
Some things I would wait for rather than push through in spring. Bare root stock is the clearest case, because once the plant has come into leaf the window has closed until the following November. Large trees and substantial shrubs are the next, because the bigger the plant, the more root system it lost or left behind, and the harder its first summer will be. Hedging is usually worth waiting for as well, both because bare root is so much cheaper across a long run and because a hedge that struggles in year one tends to stay uneven for years afterwards.
Spring is the right time to plan for autumn
There is a better use for spring than rushing plants into the ground. Spring and early summer are when the garden shows you what it actually is. You can see where the light falls, which corners stay wet, what is thriving, what has outgrown its space and what has failed. That is the information a planting plan is built from, and it is invisible in November.
Which is why spring and summer are the right time to get a planting plan done. Not the right time to plant, the right time to plan, so that you are ready to go from September onwards. If the plan is settled by August, the planting window opens with every decision already made, and September to February is spent putting plants in the ground rather than standing in a garden centre trying to work out what will suit a corner you have not properly looked at. You can read what a plan involves on what is a planting plan and do I need one, how a plan differs from a full redesign on planting plans versus garden design, and what influences the cost on planting plan cost in Ireland. The structural thinking behind all of it is set out on planting design and garden structure in Ireland.
Before Anything Goes In
Look at what you are planting into
Timing is the second question. The first is always the soil. A plant put into the ground at the perfect moment, into soil that cannot support it, will still struggle, and you will spend the next two years wondering why.
Before you plant, make sure the soil is in optimum condition. Add plenty of organic matter: homemade compost, well rotted manure, leaf mould or composted green waste all improve structure and feed the biological life that makes nutrients available to roots. If drainage is poor, work in grit as well, and be honest with yourself about how bad the drainage actually is rather than hoping the plant will cope.
Do not work soil that is saturated or frozen. You will compact it and smear its structure, and the damage lasts far longer than the inconvenience of waiting. If you want to know how to read your own ground properly, start with garden soil Ireland, and if you have heavy clay, why clay soil in Ireland needs a different approach covers the particular problems it creates for planting dates.
Give a new plant the best chance of establishing quickly
NutriChar is a biochar plant food made using a patented process, combining organic biochar with organic composted poultry manure. Worked into the soil before planting, it is fast acting and long lasting: it improves the structure and biological activity of the ground so it can hold water when your plants need it and release it when they do not. That is what allows a plant to deal with stress later, whether the stress is drought, flooding or cold. Soil first, then healthier plants, more growth, better roots and longer results.
Struggling to find the right plants?
Knowing what you want and actually tracking it down are two different jobs. Varieties go out of stock, garden centres carry what sells rather than what suits your conditions, and the substitutions people end up making are often the reason a scheme does not come together. If you have a plan for your garden and you are struggling to find all the right plants for it, get in touch. I may be able to help.
Browse By Question
When to plant in Ireland: the specific questions
The pages below cover the individual timing decisions that come up most often in Irish gardens. Every one of them is written for Irish conditions, Irish soil and Irish seasonality rather than generic advice that could apply anywhere.
Before you spend
Is it the right time to act at all?
The two questions worth settling before anything is bought or planted.
Bulbs and spring planting
Autumn planting for spring flowers
Bulbs run on their own schedule, and early is not better.
Cuttings and propagation
Timing for taking your own plants
Getting more plants from what you already have, at the right point in the year.
When timing goes wrong
Frost, stress and plants that will not settle
What it looks like when the timing or the conditions were not right.
Common Questions
Questions about planting times in Ireland
These are the questions I am asked most often about when to plant.
Is autumn really better than spring for planting in Ireland?
For trees, shrubs, hedging and perennials, yes, in my view, though both work. The soil still holds warmth in autumn, so roots keep growing after the top of the plant has gone quiet, and the rain does the watering for you. Most importantly, a shrub planted in autumn has the whole winter and spring in the ground before it meets its first summer, which is the season that now causes most of the losses in Irish gardens. Spring planting works, but the plant has built far less root system by June and you have to commit to watering it properly yourself.
What months are best for planting in Ireland?
Container grown plants can go in during any month of the year, so this is a preference rather than a rule. Mine is September to February, avoiding any spell when the ground is saturated or frozen. Bare root stock runs from November to March, so November through to February sits in both windows and is the strongest planting period of the year in most Irish gardens. March and April are perfectly possible, but you will need to water far more diligently through the season ahead.
Can I plant in winter in Ireland?
Yes, provided the ground is workable. Bare root trees, shrubs, hedging and roses are at their best planted through the winter while dormant, and container grown evergreens go in perfectly well too. What you must not do is plant into ground that is frozen solid or saturated after heavy rain. Working soil in that state damages its structure for months afterwards. In a mild Irish winter there are usually plenty of days when conditions are right.
What is bare root and why does it only have a short season?
Bare root plants are grown in open ground and lifted while dormant, then sold without a pot or compost around the roots. Because they have to be lifted out of the soil, they can only be handled while the plant is not actively growing, which is roughly November to March. They are usually much cheaper than the potted equivalent, which makes a real difference on a hedge or a run of trees. Once the plant comes into leaf the window has closed until the following autumn.
Is it too late to plant if it is already May?
Not necessarily, but the terms change. A container grown shrub or perennial planted in May will establish fine if you water it properly and consistently right through its first summer. If you cannot guarantee that, or if you are planting something large, waiting until September is the better decision. For bare root stock, May is too late and the plants will not be available anyway.
When should I decide what to plant if I want to plant this autumn?
Over the summer. The garden is at its most informative in June and July, when you can see the light, the wet corners, what is thriving and what has failed. That is when the decisions should be made, so that September is spent planting rather than deliberating. If you are planning a border or a full replant, a planting plan settles all of it before the window opens.
Does the soil need preparing before autumn planting?
Always. Work plenty of organic matter through the ground, add grit if drainage is poor, and improve the structure before anything goes in rather than afterwards. Soil with good structure holds moisture when a plant needs it and drains when it does not, and that single property is what lets a new plant cope with drought, flooding and cold. There is a full walkthrough on how to improve soil before planting.
Not sure whether to plant now or wait?
Describe your garden, your soil, what you are planning to plant and when. I will give you a direct answer for your conditions rather than a general one.
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