April is the month when sowing seeds really kicks into high gear, that is, as long as you have a greenhouse, polytunnel, or can sow indoors.
It is still a little cold to be sowing outside, and there is always the risk of a late frost, but there are a few hardy seeds you can sow outside, such as broad beans, carrots, parsnips, peas and a few others. Let’s look at the complete list of seeds to sow in April, shall we?
If you haven’t already, you want to be sowing your tomatoes as soon as possible. I started mine last month under grow lights. I know not everyone has this luxury, so you might have to wait a little longer.
However, you don’t want to leave it much later than April to start your toms, or they will be playing catch up all year. If you haven’t got them going, sow them now and place them on a sunny windowsill.
Tomatoes grown on windowsills have a habit of going leggy. If yours do this, transplant them into a larger pot and plant them deep, right up to the first true leaves.
Peppers, whether chilli or sweet, are slow-growing crops. So it is essential to start them as early as possible. However, they love the heat, so they must be started inside.
Most people will have started their peppers already, but that doesn’t mean it is too late to start some indoors. But do it sooner rather than later!
Another heat-loving crop that should be sown indoors or in a heated greenhouse. Unlike peppers, though, cucumbers grow rapidly, meaning if you start them indoors too early, you can end up with a huge plant on your hands, taking over your windowsills.
I usually find that around the end of March/beginning of April is a great time to sow cucumbers inside. This way, you end up with good-sized plants to transplant in a few weeks, but they don’t start to take over your home!
You might get away with planting cabbage outside in April, but for me, in northern England its still a little early, so I start them in modules in the greenhouse.
Again you could sow cauliflower outside and probably be fine, but I start mine in the greenhouse in modules.
Carrots can be sown outdoors in shallow drills, which is what many people will do.
I still start mine in the greenhouse, though and use a root trainer to avoid any root disturbance, which carrots hate.
April is probably your last chance to plant parsnips, so get them sown. As you might have already guessed, I use root trainers to start mine!
Beetroot can be sown undercover or straight into the ground in April. If you sow outside, then use shallow drills. If inside, then use a module tray.
Remember that each beetroot “seed” is actually a few individual seeds in a shell, and as such, you will need to thin them no matter how much care you take at sowing time.
Spouting broccoli and calabrese can be sown now. Outdoors or undercover will work for these hardy plants.
Winter squash such as butternut, crown prince and Uchiki Kuri can be sown now indoors. Squash plants are very cold-sensitive so I don’t recommend sowing in a greenhouse unless it is heated.
Even now, a late frost can kill off all your young plants, even in a greenhouse.
I really should have stuck pumpkins in with the squash above, as they are the same thing, but I wanted to include them separately for people who want to grow pumpkins for Halloween.
If you live in the north of the UK like me, then you will find large pumpkins take forever to grow and ripen up. Because of this, it is important to start them early if you want pumpkins for Halloween.
I like to start mine in April so they are ready to harvest in time. If you live further south, then May will be fine. A good way to ensure pumpkins for Halloween is to sow in both April and May to ensure you are well covered!
You can sow runner beans now but it is a little early. If you do sow them now then keep them inside for a few more weeks.
Spinach is a tough cookie and can be sown outdoors. I still find it better to sow undercover in modules and then transplant out in a few weeks time.
Another tough plant that can be started outdoors or in a greenhouse in April.
While Kale could be started outdoors, I prefer to start them in my greenhouse just to be sure. This depends a lot on the variety grown as some are very tough and would be fine outdoors.
Leeks can be sown outdoors now. Many experienced growers will have them in a seedbed to save growing room as leeks take a very long time to grow. You can achieve the same time by growing them in modules and transplanting later in the year.
Sweetcorn can be started now, but it must be indoors or in a heated greenhouse. There are some varieties, such as earlibird that are more suited to cold weather, but this is still a warmth-loving crop.
Lots of lettuces can be sown in April, so take your pick. I like to succession sow lettuce every few weeks so I always have some growing.
Rocket can be sown undercover or outdoors if you’re in a fairly mild area. I grow some in the greenhouse for a quick spring crop.
Pak choi is a spring favourite of mine and is one plant that does better in the cold than hot. So sow some now for early harvests. I like to sow in modules and grow it in my greenhouse, I can then harvest it before my tomatoes, cucumbers etc are planted out.
Peas are tough enough that they can be sown outdoors, but again I like to start mine in the greenhouse in modules before planting out later.
Another hardy plant that can be direct sown outside or started undercover and transplanted later.
Another slow-growing crop that is often started in a seed bed and later transplanted as to not take up valuable growing space. Brussels can be sown from March through to May but take a long time to reach maturity.
If you fancy getting little exotic and growing melons like me then start them indoors now. A propagator works well but I have found they germinate well just in pots, as long as they are indoors.