Last updated on June 9th, 2022
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Has your dream of gently pottering about your greenhouse as a hobby changed to a nightmare of plans and schedules for daily watering, weekly maintenance and seasonal cleanup? Let an automatic watering system look after your plant watering chores – perhaps better than you do. Ensure that your lovingly tended plants receive just the right amount of water at the times that they need it. Choosing the best automatic greenhouse watering system for your plants enables them to grow strong and healthy, saves you time and effort, and reduces your water footprint on the planet. Everyone wins.
Our review of the Best Greenhouse Watering Systems to automate watering looks at a variety of systems for performing this essential task. All but one of the models we’ve selected uses the drip watering process; the remaining watering system uses capillary action. We identify the pros and cons of each product along with a discussion of their features. Our Buyer’s Guide presents what to look for when considering the best greenhouse irrigation system for your circumstances.
Our choice for the Best Greenhouse Watering System to Automate Watering is the Hozelock Classic Micro Irrigation for Borders or up to 25 Plant Pots, with Sensor Plus Controller. This is a versatile watering system adaptable to plants in borders, planters, vegetable patches, and pretty much any kind of growing container, indoors and outside.
The Runner-up in our selection is the Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System which can be connected to a water barrel. As the name suggests, this system draws water from your rain barrel, not from the main water supply. It’s additionally eco-friendly in that it waters little and often depending on the weather, up to every three hours on extra sunny days.
BEST PICK
RUNNER UP
Greenhouse Watering Systems Reviews
1. Hozelock Classic Micro Irrigation Drip System with Sensor Plus Controller For Automatic Watering
BEST PICK
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The Hozelock Classic Micro Irrigation for Borders or up to 25 Plant Pots comes with the Sensor Plus Controller and is a versatile watering system whose use extends far beyond your greenhouse. This kit contains everything that you need to water plants in hanging baskets, veg gardens, patio pots, raised beds, or borders so you could even move it outdoors if needed or keep it set up permanently in your greenhouse.
This is mainly a tap-mounted irrigation system so you may need a garden hose to reach the outside tap on your house if your greenhouse is down at the bottom of your garden. Alternatively, you can recycle the water from your water butt instead, but it does work better from a tap because of the extra pressure.
This system uses the drip irrigation method which expert gardeners state is the most efficient way to ensure that plants receive water where and when they need it. The ‘where’ is right at the roots and the ‘when’ depends on the schedule you set the timer to. No water hangs about on the top of the soil to evaporate, ensuring that none is wasted. This traditional method is what professional nurseries choose to set up their watering systems.
The included Sensor Plus controller gives you a wide variety of watering options. A daylight sensor turns watering on at sunrise and/or sunset, this helps prevent loss through evaporation if you had to water during the day.
You can water every day to once a week (every 1,2,3,5 or 7 days). The watering session lengths are from 2 minutes for quick water up to 60 minutes for those plants that need plenty of water, perhaps ones in large pots. You can override this and water immediately from 10 minutes up to 60 minutes which is a useful feature, especially if your plants need extra water on a warm day.
You receive enough drippers to water 25 small pots. Place more than one dripper in larger pots or planters. Online reviewers state that this Hozelock watering system works best when the plant containers are fairly close together so this arrangement is ideal for a greenhouse situation.
Planning your custom irrigation system for your greenhouse and installing it takes a while. This kit comes with a lot of pieces so check that you’ve received them all before you start putting it together.
Pros
- A tap-mounted watering system that waters up to 25 plant pots in your greenhouse, greenhouse beds or outdoors.
- The drip watering method places the water slowly at the root of your plants where it’s most needed for successful growth.
- Drippers for watering individual plant pots deliver scheduled watering.
- The sensor controller sets up a watering schedule (frequency and duration) for the automatic watering of your plants.
- Includes water timer, pressure reducer and all the fittings for control, the pipeline, and the drippers that you need to immediately set-up and use the irrigation system.
Cons
- Some reports of leakage from the water pressure regulator and hose junctions. This could be down to improper set up though.
Our recommendation
The Hozelock Classic Micro Irrigation System (which comes with the Sensor Plus Controller) is an irrigation system from a company renowned for its quality garden products. This is a watering system that will suit greenhouses of all sizes and gardeners of all abilities. This system comes with everything you need to fit together and water up to 25 regular-size containers, fewer planters or large pots.
Although the sales material states that this is a tap-mounted system, it also says that you can use it on a water butt, however, from previous experience with this type of setup, the water would take longer so bear this in mind if you take this route.
The timer/controller offers a wide variety of scheduling options to suit any weather conditions. This irrigation system is also usable outdoors if you ever want to give your greenhouse a break and decide to set it up outdoors instead.
The Hozelock Classic Micro Irrigation System with the included Sensor Plus Controller is our choice for Best Greenhouse Watering System. We like its versatility, its extensive scheduling feature and its large number of drippers.
This is the automatic watering system for you if you use your greenhouse in a serious way and want help in watering your plants there. It’s also worth bearing in mind that you could automate it even more if you invested in a smart water controller that connects to your smartphone.
Read next: Best watering timers to automate watering systems
Read next: Best smart water timers to control your watering even when you are on holiday
2. Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System for Water Barrels
RUNNER UP
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The Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System for Water Barrels works in several ways to reduce your water footprint on the Earth. This system comes in useful if your greenhouse is in an area where you don’t have access to running water and need to supply your own.
This irrigation system has several interesting eco-friendly features. First of all, it uses water from your rain barrel so you don’t need to be near an outside tap although you may need a way to top up the water butt should we not have enough rain.
Recycling rainwater not only saves using tap water but also gives your plants softer water without the harsh chemicals found in tap water. Depending on whether your rainwater has passed across your roof and down a drainpipe or fallen directly into the rain barrel, it may help to grow your plants in a more organic environment.
The second eco feature is the solar panel that detects weather conditions. Your plants are watered depending on the amount of sunlight. This weather-responsive watering schedule saves on water because while plants may be watered up to every three hours on the hottest days, they won’t be given as much water on cooler and wetter days. Your plants won’t be under or over-watered which is something that is usually difficult to do with an automated system without any human intervention.
This Bosmere kit uses the drip irrigation method of watering. By placing the water directly around the roots, none is wasted. This little-and-often watering philosophy keeps the soil moist and prevents evaporation and run-off. The manufacturer states that a full 200L water butt will generally last between 7 and 10 days and this is enough for most people should they go on holiday. Your pots and planters can be up to 5m above the level of the water butt and water will still flow smoothly to them which is ideal if you plan on trailing the pipe above the plants, especially if they’re on greenhouse staging for example.
You receive 12 drippers that each handle a 20L pot. The entire system can work with 24 20L pots so you will need to buy an extension set (of 12 drippers) to use the system fully, which is a little odd, we think it should come with the 24 drippers but what they actually give you is more pipe. It’s worth mentioning you can also buy an Irrigatia Micro-Porous Hose Kit to use with this system too that is great for watering beds.
Pros
- The irrigation system waters up to 10 hanging baskets or 24 large pots of your flowers and veggies. (You will need to buy the 12 pot extension system though).
- Uses water from your water barrel so doesn’t need to be near an outside tap.
- Solar panel detects weather conditions to decide when to automatically water your plants.
- The drip watering method directly to the roots of your plants efficiently gives them the water they need for strong growth.
- Selection of water pressures delivers the right amount of water to your growing plants.
- Plant pots can be up to 5m above your water barrel for smooth water delivery even when plants are on raised beds or greenhouse staging.
- Waters up to every three hours in the summer to keep your plants from drying out.
- Audible warning (during daylight hours) if your water barrel is running low on water.
Cons
- The pump is a little noisy.
- Some may find the controls confusing and not very intuitive.
Our recommendation
The Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System for Water Barrels has several eco-friendly features. It recycles water from a rain butt (or a water tank if you don’t collect rainwater) and schedules watering sessions depending on the outside weather.
Your plants receive water more often on sunny days than on cool and rainy days. Drip irrigation delivers water efficiently to the roots of the plants and reaches pots and baskets that are up to 5m above the water butt. There’s a daytime warning and a nighttime shut-off if your barrel is running out of water.
The Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System for Water Barrels is the Runner-up in our review. We like it for its features to save water and its convenience for out-of-the-way off-the-grid places such as an allotment or a garden not near an outdoor tap.
If your greenhouse is in an unconventional place or you’re conscious about saving water, please take a long look at this irrigation system.
Read next: Best water barrels for using with water systems
3. Hozelock Grow Bag Waterer
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The Hozelock Grow Bag Waterer has a very specific use in your greenhouse, and that’s good news if any of your plants, particularly tomatoes, are developing in grow bags in the traditional way. This is an irrigation system that doesn’t need a timer, a controller, or a water pressure regulator, although one can be attached, which we talk about in a moment. You don’t need to schedule anything. It works with only natural processes and we can really say this is a fantastic system for grow bags.
The natural processes here are capillary action and osmosis. You don’t need to know about these but they are interesting. And they explain how this simple irrigation system works.
The plastic tray at the bottom contains four water spikes that pierce the base of the grow bag and go up into it. Over these spikes is the capillary mat, usually made of thick cotton or polyester. Below the tray is the 15 litre water tank that keeps the plants watered for up to 14 days, but realistically for established tomatoes, it’s probably around 3-4 days because they are greedy plants, so really it’s 3 to 14 days depending on how established your plants are.
The water gauge in the tank tells you when the water level is low. Keep checking it though because some online reviewers report that the gauge sometimes gets stuck so just watch out for this happening.
The end of the capillary mat dips down into the water and through capillary action, the water is drawn up along the length of the mat. As long as there is water in the tray and the end of the mat is in the water it stays wet. Once you put the grow bag over the spikes and push it down, the mat touches the soil. Osmosis draws the water into the soil and the soil becomes wet. The soil draws up just enough water to keep itself damp but not soaking wet. When the plants take up the water or it evaporates from the surface, it takes up more water from the mat which then draws more from the water tank.
Isn’t nature wonderful?!
The Hozelock Grow Bag Waterer is reusable from season to season. Just make sure to remove the grow bag, spikes and capillary mat and wash the spikes, tray and tank thoroughly. Store everything for winter. Replace the capillary mat every year.
Pros
- Waters plants that you’ve planted in a grow bag through capillary action without the need for a hose.
- Four water spikes pierce the bottom of the grow bag and carry the capillary mat that delivers water directly to the soil and then to the plants.
- The water reservoir holds 15L which keeps plants watered for up to 14 days.
- The water level indicator lets you know when it’s time to top up the water from a garden hose or a watering can.
- Comes with three cane holders to give your plants a stable foundation from which to grow.
- Reusable every year after you’ve removed the grow bag and cleaned the plastic tray and water tank.
Cons
- Need to regularly check the amount of water in the tank.
- The water gauge sometimes sticks.
Our recommendation
The Hozelock Grow Bag Waterer is a low-tech greenhouse irrigation system that does its function extremely well. Growing plants like tomatoes and cucumbers in grow bags has never been easier, especially plants that climb.
Most online users report that they use their grow bag waterer to grow tomatoes successfully, and some report also growing peppers or cucumbers. The four cane holders in the tray let you easily put a climbing frame or canes in. The only thing you need to do with this watering system is to remember to fill up the tank with water on a regular basis but there is also a workaround this too to automate this.
Once you have established tomato plants, the water usually lasts around 3-4 days and not 14 days which is a little misleading, however, you can attach a water timer with a hose to the system to top the water up every few days automatically. This is a great workaround if you plan on being away for more days than the water in the tank will last.
We like the Hozelock Grow Bag Waterer for its utter simplicity in performing its task well and for its reusability.
If you grow tomatoes or other climbing plants in your greenhouse, consider doing so in a grow bag and use this waterer as a simple yet effective automatic watering system. It’s also a great way to avoid overwatering as well which some automatic watering systems can do.
Read next: The best automatic watering systems for gardens
4. Hozelock Easy Drip Universal Watering Kit
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The Hozelock Easy Drip Universal Watering Kit for Beds and Borders is well suited for medium to large-sized greenhouses, as well as for the growing spaces outside in your garden. And this irrigation system grows as your gardening ambitions do. It’s modular and you can buy additional kits as your number of plants grows, or even as you expand your greenhouse itself. This system is perfect if you have plants in raised beds or planted directly in beds on the floor of the greenhouse.
Although you can think of the Easy Drip Universal Watering Kit as the base kit, it waters a wide area. Each of the 10 included drippers water up to a diameter of 100cm of soil. That’s an impressive 10m2 or so area of plants, fruits and vegetables, making it perfect for vegetable beds. The drip watering takes the water down to the roots of the plants immediately, without leaving any on the top of the plants to evaporate or runoff.
A feature of the drippers of this Hozelock Easy Drip Universal watering kit not found in any of the models in our review is that you can adjust the water flow from each dripper independently.
In most of the others, each dripper releases a standard amount of water depending on the water pressure at that point so all plants receive the same amount of water. In this universal system, there’s an individual water flow in each dripper so each plant receives the volume of water you want it to. If you notice that there’s also a difference in pressure as you go along the water hose, this gives you an extra element to play in planning the amount of water delivered.
We haven’t talked about your options for scheduling the watering sessions with this model because there aren’t any. The Hozelock Easy Drip Universal Watering Kit for Beds and Borders doesn’t come with a timer/scheduler. However, you can use any automatic water timing system with this setup and it leaves you free to choose the perfect water timer. Perhaps you have one already so don’t need to pay extra just to have a spare one lying around.
Pros
- Drip watering to the plant’s roots decreases the water lost through evaporation and run-off.
- Waters up to 10m2 with one kit – that’s a lot of veg and flowers.
- Each Easy Drip dripper has an individually adjustable water flow so that you can deliver just the right amount of water to each of your plants.
- Each of the 10 included universal drippers that water up to a diameter of 100cm of soil.
- The hose is easy to cut to set up a custom watering system designed for your own greenhouse layout.
- Modular design so you can add additional units as you increase the number of plants you grow in your greenhouse.
- A two-year guarantee for this Universal Watering Kit lets you set up your watering system confidently.
Cons
- Doesn’t have an automatic watering controller included.
Our recommendation
The Hozelock Easy Drip Universal Watering Kit for Beds and Borders irrigates a wide area of soil with just one kit. As it’s modular, extending this area is easily accomplished, so don’t feel constrained when you think about increasing your number of plants or even the size of your greenhouse. And you’re also not limited to delivering the same volume of water to each plant pot or planter; each dripper has its own adjustment for that. Irrigate cacti on the same line as thirstier plants.
We like the Hozelock Easy Drip Universal Watering Kit for Beds and Borders for its versatility and its wide area of irrigation.
If you want to automatically irrigate different types of plants at once or perhaps have seedlings and established vegetables, draw up your irrigation plan using this greenhouse watering kit and adjust as needed.
Read next – Best propagators for greenhouses
5. GARDENA Starter Automatic Watering System
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The GARDENA Starter Set Flower Pots M Automatic: The Micro-Drip System is what it says it is: a starter drip irrigation set. But this one has features that go beyond just the basics that you’d expect. It’s a tap-mounted system so you need a tap close by or an extension hose to reach out to the greenhouse.
The drip irrigation system efficiently delivers water right to the roots of the plants. This is the most effective water system and will help in reducing your water bill during the growing season. You receive nine in-line drip heads and seven end-line drip heads. Together these are enough to irrigate seven regular-size pots and three trough style planters, or some similar combination of growing containers.
If you have large pots, you may need to use more than one drip head for sufficient watering. Plan how much water each plant container needs and layout your custom irrigation system accordingly. The “Easy Control” computer delivers just the right amount of water to each drip head individually, adding extra customisation to your watering system.
You have a choice of the frequency of your watering sessions. Select from every day, every second or third day, or once a week.
It’s quick and easy to put this system together with the patented connection technology. Optional accessories include a micro mister and sprayers for alternative irrigation methods.
Pros
- An automatically controlled watering system regulates the drip heads individually so each of your plants gets just the right amount of water.
- Master Unit connects to a tap and reduces the water pressure so the water stream to your plants doesn’t damage or shock them.
- Nine in-line drip heads and seven end-line drip heads can be spread throughout your pots and troughs/planters to create your own custom watering system layout.
- Schedule watering daily, or every 2nd, 3rd, or 7th day to suit the weather forecast
Our recommendation
The GARDENA Starter Set Flower Pots M Automatic is a basic watering system with a few extras. The timer offers a selection of watering schedules, and differing amounts of water can go to each drip head which is a useful feature most other systems don’t have. There are enough drip heads to water seven pots and three planters or you could spread them along a raised bed too. Plus optional extras include micro misters and sprayers for different watering techniques so you can always extend your setup and customise as needed.
We like the GARDENA Starter Set Flower Pots M Automatic for its expansion possibilities and the quality of Gardena products are always of premium quality, much better than most other products, even Hozelock. If you’re not sure what size irrigation system you need, this one is a good place to start, and if you want a high-quality system, this is probably a good model to consider starting with.
Buyer’s Guide
The main difficulty we found in reviewing the automatic greenhouse watering systems in this review is that there’s not much information available about the various brands and models – and the information that is out there is consistent across the products.
So in this Buyer’s Guide, we give you a list of essential features and some ideas as to what to look for. We are aware that we haven’t covered all of them in our descriptions of the products in this review – we’ve just discussed the information that we could find or had experience in.
Watering delivery system type
Drip irrigation
All but one of the products in this review use the drip irrigation method. This is recommended by expert gardeners as the most efficient way of watering plants. It applies water directly to the area around the roots where it is used; no water is wasted on the soil surface where it usually evaporates. The water travels through a central hose to each of the drippers attached. The best drip irrigation systems deliver water to the plants at the times of day it’s needed the most.
Capillary action
The Hozelock Grow Bag Waterer uses a capillary mat to wick moisture to the roots of the plant using the process of osmosis. The mat, usually made of thick cotton or polyester, draws water up from a tank and into the grow bag. It’s absorbed by the soil from the bottom up, so reaches the roots first.
Other delivery types
Other greenhouse irrigation systems include:
- Sprinkler, usually for overhead watering or watering along beds.
- Seep hoses for slowly watering beds and borders.
- Misters for misting plants, usually house plants such as orchids.
Some of the automatic watering systems we review here have optional kits that add these irrigation features to your greenhouse watering system.
Timer / Sensor Controller
Many automatic greenhouse watering systems come with their own timer/controller but not all, however, it’s the best way to fully automate watering. Drip irrigation systems that don’t (for example, the Hozelock Easy Drip Universal Watering Kit for Beds and Borders) are often compatible with any third-party timer as well as timers from the same manufacturer.
When looking at a timer/controller, consider:
- How many times a day can you set the system to water your plants?
- How many times a week can you set the system?
- How long can each watering period last?
- Is there a manual override button for immediate watering?
- How easy is it to set/reset the programming?
- Can you program the timer from your smartphone / mobile device? (Bluetooth/Wi-fi?)
Note that, although it’s an automatic watering system, the Hozelock Grow Bag Waterer doesn’t need a timer, however, one can be added to automatically top up the water tank as needed. As long as the water tank has some water in it, the processes of capillary actions and of osmosis will keep the capillary mat wet and draw water into the soil. It’s this natural process that makes it automatic.
Source of water
If the greenhouse watering system draws water from the main water supply, then you may need a garden hose to reach your greenhouse from your outside tap. If the watering system recycles water from a water butt, you may still need a hose to reach the greenhouse if the water butt is under your home’s downspout and the greenhouse is not nearby. For the watering systems that use a built-in water tank, watering can be enough to fill a small tank but you have to do that quite often. Larger tanks still need a garden hose and tap to fill them.
Water pressure
In all cases, the water pressure delivered to the greenhouse irrigation system is key to how successful the watering process is. Some are designed to be used with water butts and don’t need water and work off gravity.
Pressure regulator
Most watering systems come with a regulator that tones down the water pressure from a tap. This stops the water hose from splitting from the strong pressure and avoids the drippers from blowing off the hose. Of course, if the pressure regulator is set too low, there may not be enough force to take the water all the way down the hose to the last drippers in the line.
Water hose
This is the pipe in the system through which the water passes to reach all of the pots and planters in the layout. Many greenhouse systems use a 4mm wide rubber hose, usually for drippers and some use up to 13mm. The wider the water hose, the more water can pass down to the plants at the end of the line. You can be strategic and place plants that need the most water at the start of the water line and those that like a more arid environment at the far end where they receive less water.
Drippers
In a drip irrigation watering system, there are hollow spikes that you attach to openings in the water hose and then place in the soil of each pot, planter, or trough. The water passes through these to the roots of the plants. Depending on how much water comes out of each dripper and the size of the plant and pot, you may need more than one dripper per site.
Some watering systems let you adjust the water flow for each dripper so that each plant can have exactly the right amount of water for its species and stage of growth. Most, however, don’t have this option and deliver a standard volume of water.
Battery
The pumps of most greenhouse watering arrangements operate on batteries. Check the size of the batteries that you need and whether you can use rechargeable ones. Also, check reviews about the length of battery life but they obviously vary depending on how often the water needs to come on. While many systems have battery life indicators, online reviews say that they’re not always accurate. Always replace the batteries and test out the watering system before you leave on a trip.
Final Conclusion
Don’t feel that you’re handing over the responsibility for your plant’s well-being to technology when you install an automatic greenhouse watering system. You’re making sure that they receive the irrigation they need when they need it; plus you’re not stressing yourself out trying to remember the watering schedule for each of your plants. Your plants and veg will be healthier and more nutritious (where appropriate) and you’ll enjoy them (and gardening) more. Plus there’s much more to greenhouse gardening than just delivering water – you’re still needed.
The Hozelock Classic Micro Irrigation for Borders or up to 25 Plant Pots, with Sensor Plus Controller, is our Best Pick of the systems in this review. It has it all – a customisable and versatile watering system for up to 25 plant pots, programmable sensor control, and a manual override button to start watering immediately.
Our Runner-up is the Bosmere L451 Irrigatia Sol-C24 Solar Automatic Watering System for Water Barrels. This watering system recycles the water in your water butt and uses a solar sensor to water your plants depending on the outside weather – more frequently on warmer days and not so much in damp weather.
If installing an automatic watering system has you looking at your greenhouse through new eyes, take a look at some other reviews that can help you improve the function and functionality of your greenhouse space:
The best greenhouse staging and shelving products to organise your greenhouse
The best mini greenhouses that take up a small footprint
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