by Amber

Propagation Planning: An Endless Supply of Lettuce

Crop rotation in the indoor garden is way different than the backyard gardener is used to. Outside, you plant 90% of what you’ll harvest though summer and fall in the spring. Not much need for planning or scheduling out there, but growing indoors means you’ll have to come up with a program. Your space here is much more limited, and if you’re going to enjoy a continuous harvest of fresh food, propagation needs to be taken a lot more seriously.

Lettuce is one of the most commonly grown indoor garden crops. It’s easy and has fewer demands than fruiting crops. Why? Because it’s a spring crop that needs less light power and heat, in fact high temps is not in your favor – this causes lettuces and other early season harvest plants to quickly bolt or go to seed.

The type of lettuce you grow and the stage you plan to harvest it at have a great deal to do with propagation planning. To have some fresh lettuce every week means you need to do some research. How long does it take for the cultivars you want to grow to reach the desired picking stage? Make sure you search for data in an indoor garden – AND under the conditions you have in your grow space. It will be less ‘scientifically’ controlled if you’re growing on the kitchen counter or in a windowsill than when the crop is placed in the closed environment of a grow room – be it a tent, box, closet, or a spare room in your home. How tightly sealed the closed grow space is will also have an influence on the length of time before a fresh batch of germinated seed is ready for harvesting.

Then there is the light available. Sunlight will vary in intensity, especially in winter when cloudy days are very common, not to mention the fact that the sun’s angle and color of light is not the same during the cold season as it is in spring and fall. Propagating the seed doesn’t need any light at all, but once they’ve popped light is beyond necessary. When your lettuce seedlings have produced a mature shaped leaf, they need good light for vegetative growth. Never try growing lettuces under high intensity grow lamps. It’s too powerful for easy success in most people’s indoor gardens. Still you need to have sufficient light to give them the energy needed to grow fast and lush. There won’t be much salad harvested if the light is too weak.

Baby leaf types will be the choice of many indoor home growers, because it finishes faster than head varieties. Salanova gives you the best of both worlds though with baby leaf ‘heads’ that will be ready to feast on in just 8 weeks in the hydroponic indoor garden. The stuff is wonderful tasting, gives a salad or sandwich much more crunch than most baby leaf lettuce cultivars, and unlike the straight leaf types, you can harvest from the heads as you need it. Unless it goes to seed, some new leaves will form from the crown.

So, how much lettuce does your household go through a week? You might not have the room to grow it all, but some is better than just buying it all. Germination to vegetative stage will happen in about a week if the propagation tray is on heat. Consistent moisture with a propagating dome will give you a more consistent propagation rate, as will shallow and even seeding depth. Its hard to have good success when you’ve got seedlings that need vegetative light and cells that have not popped yet… get out the saran wrap and the toothpicks! You’ve got to hold moisture on the shy seeds while the growing ones are basking in your grow lamps’ rays.

Note: Getting precise planting depth is easier in rockwool starter cubes than potting mix. Even if you’re going to use traditional container growing to bring your winter lettuce crop to harvest – you can still start seeds in rockwool. The roots will quickly go past the little cube and into potting mix or regular soil.

Once you have some lettuces approaching harvest stage, you should have a new propagation under way. A few successions, and you should have your crop rotation schedule down pat.

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The garden played a starring role from spring through fall in the house Amber was raised in. She has decades of experience growing plants from seeds and cuttings in the plot and pots.