Guy Palmer, this website’s webmaster and avid veggie grower, occasionally provides veggie growing and other gardening tips.
- Planting multiple varieties of sweetcorn.
- Why are there no heads on my cauliflowers?
- How to get more broccoli/cauliflower.
- Can worm farm worms survive in the garden?
- Growing parsnips.
- How many cauliflowers does one get?
- The results of the great tomato experiment are in!
- Seed saving from unripe tomatoes.
- Native bees and insect hotels.
- Harvesting broccoli.
- Consider planting sugar snap peas in the summer.
- How to prune raspberries.
- Is now really the right time to plant garlic?
- Rockmelons: smell their bottoms or watch them change colour?
Planting multiple varieties of sweetcorn (November 2019)
Last year, much of my sweetcorn was starchy and inedible and I have been investigating how to avoid that this year. It appears that what probably happened is that the two varieties that I was growing cross-pollinated and that cross pollination of sweetcorn often results in inedible corns. My guess is that this is something to do with the recessive nature of the different genes which make different types of sweetcorn sweet – the sweetcorn page in Wikipedia discusses some of the issues. Sweetcorn is wind pollinated so the solution is simple: if you are going to grow multiple varieties of sweetcorn, make sure that they are as far apart as possible to reduce the risk of cross pollination.
Why are there no heads on my cauliflowers? (September 2019)
I replied: “Cauliflowers are quite prone to not developing heads. It is usually a sign of stress but that stress can be of different types including: inconsistent moisture; weather that is too warm; or a lack of nutrients. I think you’re now too late to do anything about it this year – try again next year, and make sure you read this article about growing cauliflowers on our website.“
How to get more broccoli/cauliflower (September 2019)
Here is a tip from Good Life Permaculture (also see picture right): when you harvest heads of broccoli or cauliflower, cut the main stem into quarters. This encourages four smaller heads to grow back.
Can worm farm worms survive in the garden? (August 2019)
Brenda has written in to ask if you can transfer worms from worm farm into the garden. Her worm farm is full and she needs to empty it. Will the worms survive?
Here’s my answer: it depends. Compost worms are not the same as garden earthworms and, unlike earthworms, they stay on the surface. So, they can only survive if you have a surface layer of fresh organic material like manures and mulch which both provides them with food and gives them a moist environment.
Growing parsnips (May 2019)
I replied: “No, I don’t know anywhere that is selling parsnip seedlings currently. I checked with some of my local nurseries and they said that they don’t currently have any and are not planning to get any in the near future. There appear to be two reasons for this. First, most people plant parsnips in late Winter or early Spring (i.e. Aug-Oct) rather than in Autumn. Second, parsnip seedlings are very fragile and thus, at least anecdotally, susceptible to transplantation shock and so it is generally recommended that they are grown from directly sown seed (rather than either seedlings or seed trays).
“I agree that germination rates for parsnip seeds are not great. In reaction, I use fresh seed only and plant very closely (e.g. a centimetre apart), thinning them out later if needed.“
How many cauliflowers does one get? (April 2019)
I replied: “re cauliflower, yes, you only get one cauliflower per plant. Re broccoli, there are different types of broccoli. With standard broccoli, you get one main head and then, later, maybe a few more, smaller side heads. With sprouting broccoli, you get multiple, small florets. With romanesco broccoli, you only get one head per plant.“
The results of the great tomato experiment are in! (April 2019)
At the start of this warm season, my wife and I set up two identical raised beds for growing tomatoes. Let’s call them ‘neglect’ and ‘nurture’. Each bed had 8 tomato frame cages, with each bed growing the same 8 varieties of tomato. In the ‘neglect’ bed, there were 2 tomato plants per cage, no removal of side shoots, and no bird netting. In the ‘nurture’ bed, there was 1 plant per cage, regular maintenance, bird netting and the quiet singing of sweet lullabies. The question being investigated was the extent to which, in terms of tomato yield, the nurturing would offset the halving of the number of plants.
The results were rather different for the different types of tomato. For the large, beefsteak tomatoes, the ‘nurture’ bed yielded more tomatoes, even with half the number of plants, and they were better quality and larger – a major win for the ‘nurture’ bed. For the small tomatoes (say tigerella and below), neglect had less of an effect and the ‘neglect’ bed yielded more (although not twice as many) fruit and of similar quality – a win for ‘neglect’. Finally, for the sauce tomatoes (San Marzano and Roma), many in the ‘neglect’ bed, but none in the ‘nurture’ bed, suffered from blossom end rot – a win for ‘nurture’.
So, in conclusion, large beefsteak and sauce tomatoes should both be grown in ‘nurtured’ beds where the plants are widely spaced (i.e. 1 plant per cage). Small tomatoes are more tolerant of ‘neglect’ and close spacing (e.g. 2 plants per cage).
To which Karen Sutherland responded (April 2019):
Interesting experiment, and these sorts of topics are covered in (my) growing section of the Tomato book. Smaller fruited growing plants are (generally) more resistant to disease and therefore more able to be grown in less than ideal conditions, including some shade. They are therefore more suitable for growing in ‘neglect’ gardens. Larger fruited tomatoes are generally more fussy, and are best grown in ideal conditions such as your ‘nurture’ bed. Good to have these types of examples such as yours to get people thinking more.
Seed saving from unripe tomatoes (March 2019)
I was asked whether the seeds from an unripen tomato will still produce a plant. My answer is that tomatoes continue to ripen after being picked so, if there is even the slightest blush on the tomatoes, pick them and hopefully they will ripen, with the seeds also maturing. If they don’t ripen, there is still a chance that some of the seeds are viable, but only if a gel has developed around them. In addition to visual inspection, you can test for gel by trying to cut the seed with a sharp knife – if it is easily cut then there is no gel, but if the knife tends to slip off the seed then there is gel.
Native bees and insect hotels (January 2019)
It appears that native bees can take as long as a year to emerge. In January 2018, native bees visited my insect hotel and filled 8 of the holes (at a rate of roughly 1 hole per day for 8 days) – see top picture right. Over the coming months, nothing further happened (well, actually lots happened involving crickets, spiders, flies and ants, but that’s another story). In November, I happened to meet Katrina Forstner from Buzz and Dig and asked her why nothing had ever hatched. She advised me to wait until the summer. Sure enough, last week (and again at a rate of roughly 1 hole per day), all of the holes became unplugged and (presumably/hopefully) young native bees have emerged – see middle picture right.
Stop press! Yesterday, 3 or 4 days after the last hole was unplugged, I saw multiple native bees visiting the unplugged holes, going in both forwards and backwards repeatedly, and scrabbling around whilst in there. Presumably/hopefully laying eggs. See bottom picture right, which is a closeup of one of the holes. I sent this photo to Museums Victoria for identification and within the hour(!) they replied to say that it is a resin bee, genus Megachile. Or, as my wife said, what a cutie!
Harvesting broccoli (October 2018)
I replied: “I sympathise as I also sometimes have problems growing broccoli (ditto cauliflower). The broccoli we eat is the unopened flowers of the plant so if you had flowers then you must previously have had broccoli. Perhaps you were growing sprouting broccoli, where the incipient flowers (aka florets) are much more loosely grouped into heads than is the case with standard/Calabrese broccoli and therefore are more easily missed. If so, the good news is that sprouting broccoli produces new florets over time, so leave the plants in the ground and watch closely!“
Stephen also asked: “How do I know when my broccoli is ready to harvest?“
To which Guy replied: “It can be harvested any time from when the head appears to just before some flower petals start to appear or the head starts becoming looser in structure. Picking early is safer but your crop will be less. If you see even a hint of yellow, pick immediately.
Consider planting sugar snap peas in the summer (January 2018)
Our veggie patch is strictly based on a crop rotation system which means that we always have two spots available for legumes. In winter, we make the obvious choice of broad beans and peas. In summer, beans are always planted but that leaves a second spot up for grabs. Peanuts are one possibility and soybeans are another but we had difficulty sourcing either this year so we decided to consult our local nursery. They said that their experience was that sugar snap peas (but not standard garden peas) could be grown all year round. So, we planted some seedlings in December and this week, less than two months later, we have just harvested a bountiful crop.
How to prune raspberries (April 2017)
- ‘Summer bearing’, which fruit once a year, on 2nd year canes in summer.
- ‘Everbearing’, which fruit twice a year, on 2nd year canes in summer, and on 1st year canes in autumn.
Now is a good time to be pruning your raspberries because, whichever type you have, it will have finished fruiting for the year. However, the two types should be pruned differently. If you haven’t yet worked out which type you have, prune them as though they are ‘summer bearers’.
For the ‘summer bearers’: cut all the canes that have fruited down to the ground (because they won’t fruit again). If you don’t know which canes have fruited, they are the longer and thicker ones, and they often have multiple lateral branches. Thin the others to 5-7 per plant, shorten them as desired, and tie the ends to your trellis.
For the ‘everbearers’: you can prune them like the ‘summer bearers’, in which case you will get two crops (in summer and autumn), neither of which will be prolific. Alternatively, you can sacrifice next summer’s crop for a better autumn crop by simply cutting all the canes down to the ground. Clearly, the second approach would not be good if your raspberries are, in fact, ‘summer bearers’ as it will result in no fruit next year! But it is (arguably) the best approach if you want raspberries in the autumn, and it is also the quickest.
I rather like the Wikihow raspberry pruning page.
To which Heather responded (May 2017):
An alternative name for ‘everbearing raspberries’ is ‘autumn bearing raspberries’ (although, strictly speaking, ‘summer and autumn bearing raspberries’ would be more accurate).
My ‘autumn bearing raspberries’ haven’t yet finished flowering and fruiting and I am seeing big sweet berries every day at the moment. Last year, I picked my final fruit for the season on 30th July! (although they were not as sweet as the earlier ones). So it’s too early to cut these productive canes back. What I have done is tip prune them where the fruiting top segments of the canes have died but where more fruit is developing lower down these same canes. I have also removed other canes which were dead all the way down. And given the remaining canes some light fertiliser.
Is now really the right time to plant garlic? (April 2017)
In this month’s excellent Sustainable Macleod’s newsletter (click here to read the newsletter or click here to sign up for future newsletters), Robin Gale-Baker ruminated about whether the recent warm weather means that we should be deferring our garlic planting. She and I have subsequently debated the subject in more detail. It is a tricky issue, with no clear answer. The salient facts are:
- In Melbourne, garlic is usually planted in April.
- Robin thinks that the soil is currently too warm for garlic planting.
- According to Gardenate, it is ok to leave the planting until May (or even June).
- Like onions, garlic plants are sensitive to the length of the day, with the start of bulb formation (and the end of leaf growth) being triggered by a day length exceeding X hours. (This website says that X=13 and this website says that this will happen on 13th October.)
If you plant too early (i.e. when it is too warm), a risk is apparently that the resulting bulbs don’t divide into separate cloves. If you plant too late, a risk is apparently smaller bulbs (because, per day length, the garlic starts trying to form bulbs when it is too young). One potential way around this dilemma is to keep the garlic in the fridge for 30-40 days before planting. I am going to try all the possible options and will report back in due course.
Guy Palmer later added to the debate (in November 2017):
We decided to run a controlled experiment, the first results for which are now available. The first results relate to Monaro Purple hardnecks. Rows of garlic were planted two weeks apart over an 8-week period from mid April to mid June. In addition, some garlic was kept in the fridge for 40 days from mid April and then planted. All the plants died back at the same time (second half of November) and were harvested on 24th November. The key results were:
- The April plantings produced a normal number of normal-sized garlics with normal cloves.
- The May plantings produced the same results as the April plantings but in a bit less time.
- The non-refrigerated June plantings produced much smaller bulbs, half of which were not divided into cloves.
- The refrigerated June plantings (perhaps surprisingly) produced the same results as the April and May plantings.
The conclusion: continue to plant your garlic in April or May even if the weather is warm. If you forget, try putting your garlic into the fridge for a bit before planting.
Chris Newman later added to the debate (December 2017):
Chris Newman has written in to say that he is concerned that my wording might be taken to mean that people should have harvested all their garlic by now. Rather, as Chris says, one should wait until the green tops have died back and the timing of this might vary by variety, when they were planted, their watering regime, etc. Chris’s garlic has not yet reached this stage.
Chris also pointed out the aphorism: ‘plant your garlic cloves on the winter solstice (the shortest day of the year) and then harvest them on the summer solstice (the longest day of the year)’. For me, this aphorism is in the same category as ‘plant your tomatoes on Cup day’ – both timings are a month or so too late.
Finally, Chris is also growing elephant garlic, an alternative to garlic which is technically a leek (Allium ampeloprasum) rather than a garlic (Allium sativum). According to Wikipedia, elephant garlic, unlike standard garlic, does not have to be harvested each year but can be ignored and left in the ground without much risk of rotting. Chris says that the the Macleod Organic Community Garden elephant garlic has had some little babies on the side, so he will be leaving some in the ground at home to see what happens. Elephant garlic has a mild, sweet flavour that is somewhere between garlic and onion.
Guy Palmer later added to the debate (December 2017):
My Australian White hardnecks have now died back and I have therefore harvested them. Here are the results:
- Normal-sized garlics: the April plantings, the early May plantings, and the refrigerated June plantings.
- Small garlics: the late May plantings and the unrefrigerated June plantings.
So, based on my experiments, the conclusion remains: continue to plant your garlic in late April or early May even if the weather is warm. If you forget, try putting your garlic into the fridge for a bit before planting.
Rockmelons: smell their bottoms or watch them change colour? (February 2016)
Sometimes growing vegetables seems easy. Last year, we grew cucumbers. We got millions of them (well, say 50). And they grew quickly, each fruit only taking around a week to go from first appearance to full size and ready for harvesting. And (importantly), my wife had a recipe for pickling them, with results that we both thought were yummy.
Sometimes, however, things seem more difficult (and, therefore, actually more interesting!). This year, our chosen cucurbit was rockmelons. Initial developments were promising: we successfully pre-germinated the seeds, then put them into seed trays, then transplanted them to the veggie patch. But the day after transplanting them, we woke to find that all bar one had been eaten by snails. How to protect the last one? Our solution (thanks, Google) was to put copper tape (thanks, Bulleen Art & Garden) around the remaining seedling. Apparently, snails get a slight electric shock if they touch copper, so they won’t cross it.
After a few weeks of prolific growth, the flowers started appearing and we began our daily task of hand-pollination (cucurbits have separate male and female flowers). Around 10 melons appeared within the next few weeks and grew to a reasonable (i.e. eatable) size. But they didn’t look ripe and, indeed, they didn’t pass my wife’s daily smell test (smell them at the stem end to see if they have developed a sweet aroma – she calls it “smelling their bottoms”). A fortnight later, my impatience got the better of me and I picked one but it was completely unripe. Perhaps our variety never becomes sweet, I thought. Just wait some more, said my wife.
So, we waited and waited, with ritualised smelling of bottoms each day. Then suddenly (i.e. overnight) one of them completely changed colour, from green to yellow (see picture), with a noticeably sweet aroma. We picked it and, sure enough, it was as juicy and sweet as we could possibly have hoped for.
The moral is the obvious one: patience is a virtue (or, maybe, the wife is always right!).