How to grow basil indoors, and actually keep it alive

The reason the supermarket one always dies

Almost everybody has brought a pot of basil home from the shops, watched it look magnificent for four days and then collapse, and concluded that they are hopeless with herbs. They are not. That pot holds twenty or thirty seedlings crammed into a tiny amount of mix so it looks full on the shelf, and thirty root systems fighting over one handful of soil will exhaust it inside a fortnight no matter what you do.

So the first job with a supermarket pot is to pull it apart. Tip it out, ease the root ball into three or four clumps with your fingers rather than a knife, and pot each clump into its own container with fresh potting mix. It looks brutal and it works. You end up with three or four plants that each have somewhere to put their roots, instead of one that is slowly starving.

Starting from seed instead

Basil from seed is genuinely easy and it is the cheaper way in if you want more than one pot of it. Sow it shallow into seed raising mix, keep it damp rather than wet, and it wants warmth to germinate, so the top of the fridge or a sunny windowsill does more for it than anything else will.

Sweet basil is the one to start with. It is the classic big leafed basil, it is what most recipes mean when they say basil, and it is far more forgiving than the fancier varieties. Once you have kept that alive for a season, branch out.

Where to stand it

Basil wants a lot of light, six to eight hours of it, and indoors that means a north facing window if you have one, because that is the side the sun tracks across down here. An east facing window with good morning sun is the next best thing. A south facing window is not going to do it.

If you have not got a bright window, be honest with yourself about it rather than fighting it. A shadier spot suits parsley or mint much better than basil, and you will have a far better time growing the herb that matches the light you actually have. Basil in a dark kitchen goes pale and leggy and then gives up.

Keep it off a cold window pane in winter and away from the direct blast of an air conditioner, because both of those will do more damage than a slightly dim spot would.

Pots and potting mix

Drainage holes are not optional. A pot without them is a bucket, and basil in a bucket rots from the bottom up within a couple of weeks. Stand each pot on a saucer, and tip the saucer out after you water, because a pot sitting in its own runoff wicks it straight back up into the root ball.

Use a decent potting mix rather than soil out of the garden, which compacts in a pot and holds water in all the wrong places. If your mix feels heavy, a couple of handfuls of perlite through it opens it up and makes a real difference to how forgiving the pot is about watering.

Watering, which is where most of them are lost

Basil likes to be evenly damp. Not wet, and not swinging between bone dry and drowned, which is the pattern that kills more indoor herbs than anything else. Push a finger into the mix to the first knuckle, and if it is dry at that depth, water it. If it is still damp, leave it.

Water the mix rather than the leaves, and do it in the morning if you can, so any splash has the day to dry off. Damp leaves in still indoor air is how you end up with mildew.

Pruning is feeding, in a way

The more you cut basil the better it gets, which is the opposite of what most people assume, so they let it grow tall and thin and never touch it. Once the plant has two proper sets of leaves, start pinching the growing tip out just above a leaf node. Two new shoots come from that point, and doing it repeatedly is what turns one spindly stem into a bushy plant.

Pinch the flower buds off as soon as you see them. Once basil flowers it puts its energy into seed and the leaves go bitter and small, so unless you actually want the seed, take the buds off and you will keep the plant productive for months longer.

Feeding and the odd pest

A plant in a pot has only what you give it, so a light feed every few weeks through the warm months keeps it going. Go light rather than heavy, because a hard feed pushes soft sappy growth that tastes of less and attracts more aphids.

Speaking of which, aphids and the occasional spider mite are the two you will see indoors. Both come off with a spray of soapy water and a wipe of the leaf undersides, which is where they sit. Check under the leaves when you water and you will catch them early, which is the whole trick.

None of this is complicated once somebody tells you, and none of it is obvious beforehand. If a pot of yours is doing something odd, bring a photo in and we will have a look.

Shop related products

• Brunnings Seed Raising Mix 5L. Fine mix for starting basil from seed.
• Brunnings Premium Potting Mix 36L. For potting the split clumps on.
• Brunnings Perlite 5L. Work it through a heavy mix to open the drainage up.
• Seasol Seaweed Concentrate 600ml. Water it in after you have split and repotted.

Did you know we also keep Sweet Basil seed in store, along with the pots and saucers and the organic tomato and herb plant food, and none of those are on the website. Give us a ring on (08) 8536 4333 to check what is on the shelf.

The rest of the range is in garden products, and the seed packets we have listed are in D.T. Brown seeds. Bags of mix are heavy, so they can go on our local delivery, which runs Tuesdays and Thursdays, $5 around Strathalbyn and $10 on the regional run.

Keep reading

• How to grow your own salad greens at home
• Seeds or seedlings, which should you start with
• 7 habits that make a vegetable garden work

I am the kind of gardener who buys the supermarket basil anyway, purely so I can feel clever about pulling it apart in the car park.

Candeece