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Plants For Free: Are There Hidden Costs?

Growing plants from shop-bought flowers, fruit and vegetables is an appealing way to get more for less – but it’s not without its challenges. Understanding the potential plant health risks can help you grow successfully and responsibly

Growing plants directly from purchased flowers, foliage, fruit or veg is increasingly popular. Many of us enjoy the satisfaction to be gained from growing and sharing new plants. Doing so for free is almost too good an opportunity to miss. However, it’s important to be aware of the potential plant health risks and how to  protect your garden, its plants and the

biodiversity it supports. 

Plants and plant products imported to the UK and intended for planting must meet strict regulations and checks to ensure they are healthy to plant in your garden. In contrast, plants imported for eating or for decoration‚ like vegetables or cut flowers‚ pose a lower risk as they aren’t going to be grown on. This means they are checked less for plant health than plants meant for planting in your garden. So, if you plant a supermarket potato or root a stem from a bouquet, take cuttings, or use tubers or seeds from fruit or veg‚ you’re turning a low-risk plant into a higher-risk plant. These were safe for their intended purpose, but if you want to propagate them and grow them in your garden the risk of introducing a new plant health problem to your home or garden is higher than if you bought something intended for planting that had been through the necessary checks.

Dividing supermarket basil into individual plants in small terracotta pots is a simple way to grow more for free – but it’s important to be aware of potential issues
You might ask “why not have the same level of import controls for all plants and plant material, regardless of use?” This would slow the movement of food, affect cost, availability and quality across food supplies. There’s always a balance between trade and protecting the biosecurity of our food supply, plants and gardens and the wider environment.

So, is this a big fuss about nothing? It might sound unlikely but real issues are encountered more often than you may think. A good example of this would be the exotic root vegetables oca, ulluco, mashua, and yacon that were purchased on the internet and imported to the UK without any plant health checks. Tests of purchased tubers and a crop being grown in England showed that these carried a number of high-risk quarantine plant viruses and nematodes which could potentially infect a wide range of plant host species, including native species, garden plants and food crops such as potatoes. If these root crops are planted, shared or traded, any viruses or nematodes present in them can potentially be introduced and spread into the environment. In the case of the yacon, anyone growing yacon was advised not to continue cultivation once their harvest had been consumed, and further imports of yacon from outside the UK are now banned.

One of the ways to maintain a healthy garden ecosystem is by growing a wide variety of plants and by sourcing plants from a reputable UK supplier. How do we tell if a supplier is reputable? Past experience or personal recommendations can be a useful guide, as can assurance schemes such as Plant Healthy or, in the case of businesses in England and Wales selling plants online or by mail order, the list of Authorised Distance Plant Sellers, which lists plant suppliers registered with the Animal and Plant Health Agency. Careful sourcing is particularly important for food crops – and for many of these, starting with quality-assured and tested planting material of known origin helps to ensure a good harvest. Imported plants and plant material, especially from countries outside the EU, have been shown to pose the highest risk to UK plants and gardens. 

Keeping our plants and gardens healthy

You can ensure a healthy garden ecosystem and minimise the risk of introducing plant health problems to your garden by

  • Sourcing UK-origin and UK-grown material from reputable suppliers
  • Avoiding material of unknown or suspicious origin – they are often highest risk
  • ​Avoiding bringing plant material such as seeds, cuttings, bulbs, plants, cut flowers and foliage back from your travels abroad. Bring pictures and source material in country, when you get home.
  • Consider joining an allotment or garden society – these often give access to discounted plants, seed and tubers, compost and so on. 
  • Growing “free” plants in containers on hard standing, either under cover or outside, ideally on a pot saucer. This will limit the risk of new plant health issues affecting surrounding plants or the soil in your garden.

If you’re keen to try growing from shop-bought produce, some crops are safer than others when handled carefully.
 

Spuds for free

Seed potatoes have been specifically produced, inspected and tested to give us bumper potato crops. That’s why they are small, healthy, vigorous and certified virus-free. They can also be pricey too. Certainly, more per kilo than we pay for spuds at the supermarket or grocers, which are sometimes referred to as ware potatoes. Imported ware potatoes occasionally exhibit a range of pests and diseases – from scurf to more serious, quarantine diseases like the virus zebra-chip which could put your potato crop and that of other gardeners and farmers at risk. So please don’t plant imported potatoes in your garden or allotment.

If, like me, you are looking to grow potatoes and are worried about the initial cost then consider joining a local gardening or allotment group. Most benefit from discounts on supplies and sharing batches of tubers, seeds and plants can help reduce the cost significantly. If that’s not an option, then please consider growing UK-origin potatoes in containers and dispose of any green waste and growing media to the local authority composting scheme once the crop is finished.

If growing supermarket potatoes, choose UK-origin potatoes and plant them in containers to reduce the risk of introducing new pests and diseases to your garden

Exotics like ginger or lemongrass from shop-bought produce

These can be fun to grow, but shop bought exotics can pose risks. Grow them in a pot on a saucer. They’ll do better indoors or in a greenhouse or cold frame and you will limit the risk of introducing any new pests or diseases to your plants or garden this way.

Carrot and parsnip tops

Rooting carrot or parsnip tops in water can allow them to re-sprout. Potted up the resulting plants usually flower the same year, producing lovely delicate umbels, which are great for a range of insects including hoverflies. But please be careful as a number of plant viruses have been found in both carrots and parsnips imported for food. These plant viruses are harmless to us consumers but can be passed on to other plants in our gardens by sap sucking insects such as whitefly and aphids and by our hands and tools. Reduce the risk by growing the tops of UK-grown carrots and parsnips.

Carrots are cheap and easy to grow from seed. Leave carrots to grow in the ground for a second year and they will produce delicate umbels of flowers which are attractive to pollinators

Brilliant berries – raspberries, strawberries and more

Some online gardeners advocate harvesting and growing seed from purchased fruits such as raspberries and strawberries but bear in mind that seeds can also carry plant health problems such as viruses which can reduce plant vigour and berry yield. For best results, start with disease-free, certified stock. You can always propagate extra plants from these by growing healthy suckers, or by taking hardwood cuttings. Raspberries have a tendency to accumulate viruses. They are very popular with sap feeders like whitefly that can transfer viruses from plant to plant as they feed. When we propagate plants from splits or suckers these viruses remain. For this reason, gardeners normally replace raspberries with fresh certified stocks every 7 to 12 years.

Raspberries can harbour viruses that build up over time, reducing vigour and fruit yield if plants are propagated from infected stock

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