Like many other gardeners, I caught the succulent-growing bug some years back. I find myself in constant awe of the colors and shapes of these magnificent plants. Additionally, as a died-in-the-wool greenhouse gardener it’s natural that I’ve since experimented with growing many different succulents in my greenhouse.
In this article I’m going to discuss my personal experiences and aim to answer the question of whether greenhouses are good for succulents.
Greenhouses for Succulents in Summer
First the good news – greenhouses can be very good for growing succulents in the warmer months of spring, summer and perhaps even fall. There are many reasons for this but let me lay out some of the biggest benefits I’ve experienced so far…
Most succulents are cold-sensitive and tend to grow best when kept comfortably warm. This is the primary reason why many of us in temperate areas consider succulents more of a houseplant than a garden plant. Sure, many will happily live outside in pots in fine weather, but most will need to be brought indoors for protection over the winter.
A greenhouse, by its very nature, tends to get warmer than the ambient temperature outside. And this additional warmth can really act as a growth catalyst for your succulents. I’ve tried growing specimens outside and inside, and my experience is that those grown in the warm greenhouse tend to grow far more rapidly (and more vigorously) than those outside.
Excellent Light Intensity
Succulents are typically well-adjusted to bright, sunny, exposed growing conditions. Many of them come from arid, desert-like regions after all. This means the more sunlight you can give them (within reason) the better.
A well-positioned greenhouse will receive sunlight from dawn to dusk, giving your succulents all the light they need to stay healthy and put on a real show.
This is rather different to many windowsills, which may only receive sunlight for a short period each day. Even a south-facing windowsill is unlikely to receive as much sunlight as your greenhouse, thanks to it’s all-glass (or all-plastic) construction.
Dry Air Minimizes Rotting
The fact that greenhouses get so warm in summer means that it is normal to ventilate them well. Doors and roof vents are left open, and any humid air quickly escapes. This means that the inside of a greenhouse in summer can be quite dry.
Of course, this dry air suits most succulents well. It means you can water safely, knowing that the compost will quickly dry out again, thus avoiding the risk of your beloved plants rotting.
Indeed, you may find that your succulents need more water than they did when kept on your windowsill so be sure to adjust your watering routine as necessary.
Greater Protection from Damage
One of my favorite things about greenhouse gardening is the protection it affords my plants. Those in the greenhouse just seem healthier and more “perfect” as they’ve been less-affected by heavy winds, rainfall, and garden pests like birds or caterpillars.
Succulents can be more sensitive than many other plants, so this extra protection is well received by them, and ensures your specimens look their best at all times.
Greenhouses for Succulents in Winter
Growing succulents in your greenhouse in winter brings with it a unique number of challenges. These are far from insurmountable but do require extra effort and vigilance if your plants are to thrive in the coldest months.
Temperatures May Get Low
Unheated greenhouses can get pretty cold in the winter, especially at night. In particularly harsh weather they may even drop below freezing, and of course this can put many succulents at risk.
Before committing to leaving succulents in a greenhouse all winter you should carefully research their minimum growing requirements. Only very few will tolerate a “temperate” winter climate – though there are a handful of more hardy succulents.
Alternatively it is of course possible to add heating to your greenhouse. From paraffin heaters to electric fan heaters, there are more options than ever before to keep your plants toasty warm even in the worst weather.
The key is doing your research well in advance and buying any equipment you’re going to need so you’re prepared for any surprise cold snaps.
High Humidity & Damp Conditions are a Risk
It’s not just low temperatures that can harm your succulents. Just as dangerous are continuous damp conditions. Succulents kept in these conditions can start to discolor, rot, droop and may even die.
The combination of heavy winter rainfall, combined with low ventilation levels and low air temperatures, can make greenhouses very damp in winter. As with other issues, there are of course solutions, but overly-damp conditions are a major concern for greenhouse succulent growers.
Tips for Growing Succulents in a Greenhouse
If you decide that you’d like to try growing succulents in a greenhouse year-round then a number of tips will help to increase your chances of success…
Raise Plants Off the Ground
Plants placed on the ground in your greenhouse are more likely to get chilled and to absorb excessive moisture. Placing succulents onto a table or greenhouse staging helps to reduce these risks and facilitates proper drainage in the winter.
Reduce Watering in Winter
Try to keep watering to an absolute minimum in winter. This not only reduces the chances of your succulents rotting, but will also reduce moisture-levels in the air.
Ventilate When Appropriate
It can be tempting to shut up your greenhouse in the fall and to barely open it to the outside until the spring sunshine arrives. However ventilation is still important even in the winter months.
There are two simple solutions. Firstly, consider opening the doors and/or roof vents on mild, calm days to permit natural air movement. Secondly, an electric fan heater can help to move air around your greenhouse, reducing the sort of damp, stagnant air that causes problems with succulents.
Consider Some Supplementary Heating
Greenhouse heaters can help to keep temperatures above freezing, as well as reducing overly humid conditions. Of course there is a cost to heat greenhouses so be mindful of this if you consider such an option.
Paraffin heaters are usually quite reasonably-priced to purchase, though ensure you keep spare paraffin to hand for the worst of the winter months.
Conclusion: Are Greenhouses Good for Succulents?
Answering the question as to whether greenhouses are good for succulents is not easy. As you can see, there is no simple yes/no answer. While greenhouses can certainly be fantastic for succulents in summer, the winter months can be far more challenging.
The easiest solution is clearly to bring your succulents back indoors over the winter, where temperatures are higher and moisture levels are lower.
That’s not to say that succulents can’t be grown in greenhouses year round, just that you’ll have some unique challenges to face. Many botanical gardens do indeed leave their succulents under cover all year round so this is certainly possible if you’re willing to consider adding suitable heating and ventilation.
Generally speaking an unheated greenhouse probably isn’t the most suitable winter environment for succulents. While I do know a few people who have succeeded, they have still lost a number of plants in harsh winters, and many of the surviving specimens show unfortunate damage such as rotten brown areas.
In the end all I can do is give you the facts – it’s then up to you to decide if you’re willing to invest the time, money and effort into making your greenhouse a comfortable place for your beloved succulents.
Whatever you decide may I wish you the best of luck. Oh, and please leave any experiences you’ve had or questions you may have in the comments section below so we can all learn from one another.