Helping hedgehogs, DIY potting mix, and crispy cabbages

I think it was quite late one night and there was a knock at the door and I was thinking oh my gosh who's this? And it was my neighbour and he was like he just said look there's a hedgehog outside! So we were like down sort of crawling through all the shrubs and things and basically yeah there was this hedgehog in the garden which was just absolutely brilliant so that was I think that was kind of last year so I think it's been hibernating. Yeah there's hedgehogs in the area which is fantastic and it's a very busy urban area you know we're talking very small gardens we're not talking big kind of mansions and fields and things and it just goes to show that hedgehogs are very adaptable very resilient and actually they can survive in lots of different places. That was Grace Johnson from the Hedgehog Street campaign. In a moment she'll be telling us more about what we can all do to support the recovery of hedgehog populations right where they need it most in our gardens. And it's not just hedgehogs stirring back into life. At this time of year Queen Bumblebees are emerging, lady birds are on the move and for the birds singing their hearts out nest building is already well underway. Across the garden there's a real sense of momentum. Some trees are bursting into blossom, others are unfurling fresh new leaves. Bluebells, dandelions and tulips are all in their splendour and everything feels poised on the brink of abundance. Which of course means it's a busy time in the potting shed too. Growing from seed is one of the most affordable ways to fill your garden for the season ahead. An RHS horticultural advisor Jenny Bowden will be joining us to share how you can even make your own potting mix from scratch at home. And later on Liz Mooney will be heading down to the veg patch with everything you need to know about growing cabbages. All this coming up on Gardening with the RHS with me Guy Barter. We are right in the middle of peak sowing season and while plenty of things are fairly unfast seen can be sown directly outdoors, many require a bit more TLC to get off to a good start. Take your cucumbers, marigolds and zinnias. All these are tender and need to get started in the greenhouse or a sunny windowsill to avoid frosts and the voracious appetite of slugs. This usually means sowing into seed trays or pots, using a specialist seed or multi-purpose potting compost, something you can easily pick up locally. But if you fancy a budget friendly plastic free and a truly local option, why not try making your own? Jenny Bowden, one of the RHS's horticultural advisors, has been doing just that, experimenting with homemade potting compost in her south east England garden. We caught up with her to hear more about what she's been trying and the successes she's had along the way. I've been reworking the garden recently, extending flowerbeds out, getting rid of the lawn and really getting into this idea of sand gardening. And I've been aiming to grow more of what does well already and multiplying plants up, but there are plenty of gaps because I've extended the beds out and I've been looking at growing quite a few annuals and perennials in preparation, partly because I'm a little bit stingy and I can't really afford to buy them as big sized plants. And so I've been growing quite a few things from seed, which has been, I mean I've always grown things from seed, but it's still been quite an experiment because I've been experimenting with the compost to actually plant them in. I thought, well, let's mix my own. It does make sense to try to grow things in pots in the medium that they're actually going to be growing in the open beds. That makes sense in one's mind, but it's not actually as simple as that and this is why potting compost is sold and seed compost because it's highly engineered and it's engineered for a reason. If you just, for example, in my case, have sandy soil and you fill a pot with sandy soil, it is nothing like planting that plant or planting those seeds into the open ground because you have capillary action and you have gravity. So when things get watered, it goes right through and there's a constant movement of water through. If you've just put the water into a pot, it can actually gather and sort of sit there. Everything really sulk. You can even end up with algae on the surface. It just does not drain in the same way. The compost needed for seed, they need a fair amount of oxygen, a nice sort of airy mix, which is still fine so that they've got the oxygen in contact with their tiny roots, even though this isn't necessarily how they might be in the wild out in the open. Just being in that pot means that you've got to have that sort of artificially created air spaces. The most disappointing thing sometimes about growing seeds are damping off diseases, which is basically when your little seedling comes up and it all looks very hopeful and encouraging and then it just falls over and that is a damping off disease and it can be caused by disease in the soil called fusarium, for example. That's just one of them. And it's also a reason why it's always best to water seedlings with tap water rather than water but water as well because it can potentially have that in it. You need a good mix of, for example, garden soil with sand mixed in, like coarse sand, horticultural sand, and also ideally leaf mould. Leaf mould is very easy to make. It takes about a year but you can put them into a bin liner, stick a few holes into the bin liner, tie it up and after a year you have leaf mould. So you would sieve that and you'd make a mixture of these things and that is roughly the way to make compost for seeding. You can experiment with this. My mix was rather heavy. My soil is sandy and I thought that would be perfect but I didn't put enough organic matter with it. But you know, everything grew. It did all grow because I was quite careful with the watering. But a classic mix would be 50% good garden soil, 25% coarse sand and 25% leaf mould. People talk about using homemade garden compost or leaf mould as being interchangeable. Leaf mould is really low in nutrients and it also has fewer damping off diseases in it so it's a little bit more inert in terms of any possible diseases you could get that could jeopardise your young plants or your seedlings. It's very good for soil structure, for the compost structure that you're creating but it's low in nutrients. Homemade garden compost can have quite a lot of nutrition in it. You could potentially wash it through just to get rid of any salts but to be honest it should work pretty well as well. It's often said to pasteurise the top soil which isn't the same as sterilising. Pasteurising is a slightly lower temperature. Now you can actually do that in your oven at home. You can get a tray and put a few centimetres in the bottom of the tray, about 7 centimetres and about 3 inches. And you heat the oven up to 100 degree centigrade, cover the tray with foil and you actually want to get the soil in the trays to a temperature of between 82 to 90 degree centigrade and even test it with a thermometer and you cook it for 30 minutes and it can smell quite funky. So you can have this lingering smell of cooking top soil in your kitchen. Now this would be absolutely the golden standard and it can actually help prevent damping off of seedlings. I used my mix in the house so the soil never got really cold, nothing really soaked. The ambient temperature was quite warm. I think if you're growing in a cold greenhouse things are likely to sulk a bit more in a cold wet soil that isn't a good structure. So I didn't pasteurise mine but I'm giving best practice but I think it's all a bit of a movable feast with the mix that you use and it also depends on what your garden soil is like as to how much organic matter it might already have in it as to how much extra you need to add in. So I think my main piece of advice would probably be to do it and to be quite open minded about it and experiment and even perhaps buy a good seed compost and do a little comparison to see how you're doing. I have done that as well and I found that my mix wasn't so bad after all so it ended up being quite versatile. What was lovely about the Bort mix was that it was just such a lovely texture, it just settles beautifully when you water it with the rows of a watering can. I think mine was slightly lumpier because of the sieve that I used for the organic matter but it worked. I have to say I've been really quite pleased with myself this year because having made my own compost I'm pleased that there's been no plastic bags to consider what to do with or try to recycle. There's been no miles involved in going to the garden centre to actually buy it. All the ingredients have come from my own garden and it just feels like that kind of closed loop is really satisfying and I think with the Pete Free initiative that's going on at the moment, the fantastic move to not use Pete in horticulture has really made me think and made all us gardeners think about it and actually it pushes you into being quite creative and so that's all been good so it's been a good spring so far. Thanks so much to Jenny there. Last week we heard from Grace Johnson of the Hedgehog Street campaign about the challenges facing Britain's hedgehogs. Over the past two decades their numbers have declined dramatically. A third of all rural hedgehogs have disappeared in the last 20 years driven by habitat loss, increasing road traffic and a dwindling food supply. One glimmer of hope however resides in our gardens where hedgehog numbers are showing signs of recovery. Now Grace is back with some simple practical ways we can all help, whether it's making your garden more hedgehog friendly or joining in with citizen science. There are plenty of easy and rewarding ways to get involved. As much as it is humans that have modified the landscape and you know we've made it a bit inhospitable for hedgehogs, what we've got in gardens is actually a lot of people helping them. People really love hedgehogs and a lot of people are making changes to the garden that are really helping which is fantastic. The data that we have is indicating that hedgehogs are faring better in urban and suburban areas which is interesting, it's kind of the opposite of what you'd think that it would be. We sort of call them micro-habitats so it's a bit like in one garden they might find a log pile with loads of beetles and a bowl of water and then they go to the next garden and it's got short grass where they can forage for earthworms because really a lot of what hedgehogs need is variety and the gardens are giving them that. They're sort of travelling between gardens, between parks, finding all of the different things that they need, all of their different insects, they're finding you know other hedgehogs, they're finding mates, they're finding nesting sites and actually gardens are becoming this real sort of stronghold for them. Because hedgehogs are what's called an indicator species it can tell us that actually the environment in your garden is quite healthy so it means that you've got a good population of invertebrates, it means that the soil conditions good because it's hosting all of these invertebrates so it's a really good sign if you've got hedgehogs in the garden and you know they're not going to be causing any harm, if anything they're going to be helping to maintain a balanced ecosystem, they're going to be eating any excess of things like caterpillars, they're not really going to be eating things like slugs and snails, they don't feature that highly on the menu but they're just going to be eating things like caterpillars, earthworms, earwigs and just maintaining a nice stable ecological balance in the garden. It's a bit tricky to tell if you've got hedgehogs in the garden because they are of course nocturnal but there's a few ways that you can check if they're in your local area so as part of the hedgehog street campaign we run the big hedgehog map so people can log sightings on there but as well as that you can have a look at the sightings that have been logged in your local area so I actually did this last summer because I saw a hedgehog outside my house and realised that actually people have been seeing hedgehogs for the last few months so have a look at the big hedgehog map, you can look for the droppings in the garden maybe not the most fun job looking for the droppings outside but that can be a really good way to tell so what you're looking for is kind of small dark pellets about the size of your thumb or your little finger and what you'd be looking for within that would be little shiny segments so that's the undigestible parts of the insects, the invertebrates that they're eating. Wildlife cameras is a great one, a lot of people have those nowadays and that's a really nice way to see whether there's hedgehogs there but also that's going to tell you do you have anything else visiting and then you can use things like footprint tunnels so this might be a little bit more involved but just if people are particularly keen what it is you put something like meaty cat or dog food in this tunnel to attract hedgehogs that's the kind of bait to bring them in and then you use kind of inky pads on either side of the food and then on either side of that at either end of the tunnel you just put bits of paper so the idea is that hedgehogs walk through the ink it's like natural ink it's just sort of charcoal and vegetable oil I think it is when you mix them together they have some of the food get the ink all over their paws and then the idea is that they walk across the paper and you can see their footprints and you can identify different species based on their footprints that's quite a nice way to tell but there's lots more information online if anybody wanted to actually have a go at that one. So there's lots of different ways to help hedgehogs in the garden so first and foremost think about access can they actually get into your gardens. Hedgehog highways I think most people have heard of those now which is brilliant so that's small gaps in fences aimed for around 13 centimetres up and across talking to neighbours trying to create hedgehog highways along the entire street linking front gardens to back gardens via side gates things like that just really think about access can hedgehogs get into my garden and then the next couple of things to think about are can I bed and breakfast so in terms of bed you want them to have natural sort of nesting opportunities so think about low shrubs that they're going to be able to shelter under nice kind of thick hedges that's going to be create a really nice kind of dense structure for them to nest under make sure there's lots of leaves so when the leaves fall in the autumn you can leave those out on the lawn and hedgehogs are going to be gathering those up to build nests they do often build nests under things like sheds or decking those can be really good areas for them you could put in a dedicated hedgehog house which is a really nice way to help you can build those we've got instructions on the hedgehog street website or you can buy them online that's a really nice way to think about kind of bed where are those quiet sheltered areas that they can build their nests and then think about breakfast so bed and breakfast the breakfast side of it is we want those creepy crawlies we want the invertebrates in the garden so think about having as much variety as possible things like log piles are really good if you lift up one of the logs there's all kinds of things crawling around that's all hedgehog food leaf piles are really good as well compost heaps absolutely brilliant that's sort of bed and breakfast for hedgehogs they can nest in there something like a wildlife pond is a brilliant idea as well that's going to benefit so many different things just make sure it's got a bit of a sloped edge or a ramp or something like that because hedgehogs can unfortunately fall in yeah it's that access make sure they can get in think about bed and breakfast so nice nesting opportunities and areas that they can forage for food and all of those things together are going to create this brilliant environment for them leaving food out is a really nice way to help hedgehogs the their natural diet it's those creepy crawlies in the garden but unfortunately they are struggling they're in decline so a nice way to top up that natural food is with something like meaty cat or dog food it supplements that natural diet the natural diet's the most important thing i think what we wouldn't want is a completely paved garden with a bowl of cat food that's not really the right kind of balance we want to make sure there's that natural food for them but there's a few things to just be conscious of so just make sure that you're cleaning any bowls to prevent any disease transmissions because it's bringing together a species that doesn't normally come into that much contact with each other you know they are solitary then you can think about feeding stations as well because if you put in out cat food there's a good chance that cats are gonna obviously come and pinch it so you can use one of those plastic under bed storage boxes cut a little hole out of that a lot of people do that and pop the food inside and that's quite a nice way just to keep anything like cats and foxes away from it and just make sure you're only feeding hedgehogs one of the key elements of our work at the moment is the national hedgehog monitoring program and we're essentially using networks of camera traps all over britain to estimate how many hedgehogs are in a given area so the survey work that we've done previously has told us where hedgehogs are but this new methodology is telling us how many there are previously we wouldn't know that a population was struggling until it had disappeared when we've got the numbers of hedgehogs from this new project it's going to allow us to track the numbers year on year across different habitat types and crucially it's going to create this really good feedback loop of the conservation work that we're doing so obviously we've got these camera traps all over britain but they're also triggered by things like badgers, deer, squirrels, basically absolutely anything that's out and about so we get all of these images together we screen them using AI so the AI says you know I think that's a hedgehog I think that's a badger but then we need people as well we need citizen scientists to log in and basically help us go through these pictures and it's actually quite a nice little quiet afternoon activity I always end up doing it on a Friday afternoon when I'm kind of wrapping things up from the week you literally just click through the pictures if you see a badger you click badger if you see a hedgehog you click hedgehog and it ends up being quite addictive actually you end up doing it for sort of more time than you think you're going to but that's a really nice accessible way to get involved but actually we do really need that help because we've got all of these cameras they're producing millions and millions of images and we need lots of people to log in and help and it's a really fantastic way to get involved and help us with this important monitoring work it's absolutely fantastic if you've got hedgehogs in the garden they're just a brilliant species to see all of the changes that you make to help hedgehogs all of these small simple cheap things in the garden they're also going to make a huge difference to lots of other species as well your pollinators your other mammals bats birds butterflies all sorts of things are going to really benefit as well and as an indicator species if you spot a hedgehog in the garden it's really good news it means that the your garden and the wider environment are healthy they're supporting a good ecosystem and one that's able to allow hedgehogs to thrive which is fantastic so yeah keep up all of that good work and hopefully when we hit summer you'll hear the pitter patter of their little hoglet feet in the garden as well Thanks so much to Grace there do check out the links in the show notes I'm delighted to say we have hedgehogs in my corner of Surrey they roam from garden to garden along the railway bank and underneath the fences when they come in they absolutely delight the cats who just can't believe what they're seeing and follow the hedgehogs around the garden the hedgehogs don't seem terribly phased and finally let's talk cabbages we're joined again by RHS whistly's Liz Mooney who is a firm fan of these sometimes unfairly maligned vegetables cabbages are sometimes a crop people don't particularly want to grow either because they've heard they're difficult to grow or because they've been put off eating cabbage by some soggy school dinners but I really do like growing cabbage I find a fresh white cabbage is really nice to eat a fresh and void cabbage harvested in winter or I'm a particular fan of red cabbage which you braise down with sort of onion and cooking apple and that sort of thing and it's just so tasty on the plate as an addition you don't just have to eat it as cabbage and have chopped it up into a crunchy cold slaw or anything like that there are lots of different ways to use them when I was getting into horticulture and grow your own I sort of viewed cabbages as a classic winter crop and indeed they are there are some varieties that are really good for overwintering and giving you that fresh harvest at slightly more challenging times of year but there are also cabbages that are great for sowing more in the spring for harvesting in late summer autumn so it's worth checking the varieties because not all varieties are fully winter hardy and will stand those winter frosts one of my favourites for growing more for sort of these late summer autumn harvest is a variety called greyhound which forms this lovely white head and I will grow that most years it's also worth bearing in mind that a lot of the red cabbages are not quite so winter hardy as the others so I will tend to grow red cabbage for an autumn harvest in around October and then you're looking at for some white cabbages and also some savoy cabbages and some winter green types that are better for wanting to then grow through the winter in terms of sowing in the spring you're looking at things like greyhound as I mentioned is a really good one I would also be heading towards maybe in slightly later spring sowing some of those red cabbages so red jewels a really good one, buscaro, primaro they're really good ones to sow for that sort of more late summer autumn harvest and then when we're heading into the winter I'll go I mean always keep an eye out for some of the savoy cabbages and some of the names will give you a hint for the fact that they're good for over winter so for savoy cabbages you've got things like Alaska is a really good one, January King is a really good one to go for for growing over those winter months or something like winter jewel is a sort of more it's a spring green cabbage so you wouldn't expect that variety to form the classic cabbage head the tight head you would expect it just to be a leafy green cabbage crop we actually harvested that in the garden in early March this year so I'd planted that out in late summer and we only harvested it in March the timing will depend on what variety you're growing whether you're sowing it in March April for some of the late summer autumn varieties or whether you're sowing a bit later in the year to plant out in June early July for some of those overwintering varieties you can even push a little later than that if you want to but the process for sowing planting growing is similar for all of them so I will generally start my cabbages inside the reason being they are very prone to being nibbled on by slugs so I want to grow them on until they're a little larger they've got a little bit more resilience to go out in the garden so also I have a little module trays seed trays they will end up being pricked out and grown on in nine centimetre pots until they've got several leaves at which point we'll plant them out in the ground so when you plant your cabbages in the ground like all things in the brassica family which also includes things like sprouts cauliflower broccoli you want to firm them in really well at planting time you can bury the base of the stem to sort of get them a bit firmer in the ground because if they've got too much rock if they're not secure enough in the ground that can inhibit variability to form good heads so firm them in really well I will tend to put a little cabbage collar around the base of them just a little disc of cardboard and what that does is it stops an insect called the cabbage root fly laying its eggs right around the base of the plant because if it does the cabbage root fly it hatches the eggs hatch and they eat away the roots of the cabbage which you obviously don't want because it won't grow very well so that little disc of cardboard is a really simple way to keep that off now these cabbages are also very prone to be eaten by lots of other things you can tell brassicas are tasty because lots of things want to eat them so I will protect all of my cabbages with butterfly netting so whether that's a hoops or a walk-in brassica cage or whatever you happen to have to support that brassica netting the brassica netting needs to be butterfly proof not just bird proof butterfly proof because you're stopping the cabbage caterpillar from getting at them because the large cabbage white small cabbage white cabbage moth all of their caterpillars if laid on the plant will hatch and eat your plant the butterfly netting is a really simple way of keeping the moth just make sure the plants aren't too close to the butterfly netting because the butterflies can perch on the outside of the netting and if the cabbage is touching it they can just lay their eggs through the netting you'll know when to harvest your cabbage because you'll be able to look at it and you'll see what sort of ahead it's formed through the growing season yeah you'll be you'll have removed some of the lower leaves as they sort of turned yellow and fallen off but you should still have this central heart of the cabbage and you harvest it when it's ready you can tell it's going over a bit because sometimes the heads will start to split and that's an indication that you you need to harvest it straight away it's still perfectly edible at that stage but you just don't want to leave it any longer so to harvest the cabbage I'll just go in with a sharp knife or a pair of secateurs and cut just below the head now you can then remove the stalk from the ground again I would just cut it at ground level leave the roots of the soil to rot down or if you don't have anything else to go straight into that space you can remove the head and then if you cut a little cross into the top of that stalk sometimes it can encourage it to sort of reshoot send out some more cabbage leaves and things you won't get another full-sized head but you might be able to get another little second crop off it at that stage in terms of maintenance they're short enough not to need any staking and they don't need masses of watering but you don't want to let them dry out too much once they're established in the ground generally they can cope but if it's a really hot dry summer you will want to give them a bit of water maybe once a week or something but give them a bit more than that while they're establishing and getting growing and then I will just tidy them up so the lower leaves as they turn yellow and so they're not really photosynthesizing they're not doing any particular good to the plant at that stage so I will tend to remove them partly that's an aesthetic thing but also it's about having fallen foliage lying on the ground can act as a magnet to slugs and things so we're just trying to keep them off the plants. I would really encourage you to give growing cabbages a grow they along with other brassicas can be a bit trickier than other crops because there are so many other things out there that want to try and eat them but with a few simple tricks and tips you can grow them successfully and get fresh cabbages to grow and eat and add to your nutritious diet. Thanks to Liz there all good advice I too love cabbages I grow a lot of cabbages I don't really grow F1 hybrids because they produce a heavier crop and they take up less space and I particularly like red cabbages I'm with Liz on red cabbages I can't seem to grow a good red cabbage though it's been for the last five years I've had real difficulties so I'm growing lots of different red cabbages this year and trying different methods they're all sown already along with my summer cabbages and my white storing cabbages so fingers crossed I managed producer a good crop waiting for my attention in the garden shed and my autumn and winter cabbages lots of Savoy's white cabbages green cabbages all sorts of cabbages not too many though because I grow a lot of cauliflower I absolutely adore cauliflower growing but I do like to have plenty of cabbage as well six plants is enough for me of each different kind and then I eat them all winter and in fact I've still got two Savoy cabbages now that are waiting for my attention down on the allotment but after that we'll be cabbage free until the ones that are currently in the greenhouse form their hearts in June July I too am with Liz on the value of cabbages and urge you to plant some they're a very rewarding crop as the emperor Diocletians said when he was asked if he missed being emperor after retirement he said ah but have you seen my cabbages or words to that effect that's good enough for me that's just about all we have time for this week so from me Guy Barter goodbye and thanks for listening you've just been listening to brilliant advice from our experts now you can take your gardening even further with the RHS grow app RHS grow is your companion for creating a garden that works in harmony with nature this earth day explore ways to support wildlife earn badges as you help your local ecosystem thrive and discover inspiration tailored to your space with plant identification plant combination ideas and handy care tip reminders straight to your phone the RHS grow app makes it easier than ever to nurture a beautiful nature friendly garden