In my mind there are only 3 types of gardens bed – Containers, Raised beds, and in-ground.
Containers – this is ideal for the balcony gardener. Containers need to be filled up with a substrate (growing medium) and unfortunately you will probably have to buy this. There are plenty of stores that supply containers as well as bags of soil to grow in. I recommend nothing synthetic and to support your local garden centers over big box stores. Get creative with containers as they are expensive – old milk/juice containers, 5 gallon buckets, trashcans, etc. can still do the job. Containers are fun in that you control the growing medium entirely (unlike in ground gardens) but require more water and you limit yourself to shallow rooted plants. I do not have a wealth of experience with containers so I will end the section here.
Raised beds – a very popular choice. Raised beds are constructed from a frame, often wooden, and filled with soil. This requires a large amount of soil often meaning you will have to buy in bulk. Alternatively, you could make a lot of compost, but this will take a considerable about of time. Raised beds differ from containers since they have no bottom and will grow both above ground, and in the ground. These are a fantastic way to control weeds, nutrient levels, and you get to start with good fine soil – much easier for spreading seed. Raised beds do require more frequent watering as they are above the true soil line and drain better. This can be a good or bad thing. They can also get quite expensive.
In-Ground – My favorite. If you are growing in raised beds or containers, you are not really improving the native soil. Some soils like hard clay or sand can be very difficult to work in but adding OM makes it all much easier. A poorly drained soil drains better with OM, and a quickly draining dry soil holds more moisture with OM – hence the importance of composting. Double-digging is a popular way to get these started (a great book on the matter is How to Grow More Vegetables by John Jevons).
Nutrients and pH:
I actually don’t want you worrying about this. As I said earlier, Humic acid helps buffer pH for plants making it something not to really focus on. The exception is certain perennials like blueberries which really need a good acidic soil. There are many guides online as to how you can acidify the soil (or make it more alkaline). On this I am no expert.
As far as nutrients go adding compost will fix the majority of your problems. If you have what you believe to be good rich soil and still have issues growing plants, I suggest a soil test and see if you are deficient in something necessary. Plants can do really amazing things like pull nutrients from the subsoil, but they cannot pull something you do not have out of the ground. If you have no magnesium for example, your plants will not be able to just make it. I have personally never run into this problem, however.
NPK – Nitrogen, Phosphorus, and potassium. These are the big 3 that people always recommend adding to plants and they are quite necessary. However, this is often done at the expense of draining the soil of carbon and trace minerals which can be added through OM. Gardeners and farmers tend to have an over-obsession with nitrogen which is really like protein for a human. It helps plants get bigger and stronger. Keep in mind that every 1 part of nitrogen added uses 15 parts of carbon in the soil, this means the more liberal you are with nitrogen fertilizer – the less carbon and OM will be in the soil and the more OM you will need to add every year. There are plenty of ways to organically add N to the soil like alfalfa (and other legumes) and aged manure. Please do not jump on the petroleum bandwagon.
Ah, yes! We finally get down to the plants! I will tell you my secret to choosing plants – grow what you want. That’s it. Your land might be perfectly suited for cabbage, but don’t grow it if you don’t want to eat it. Find what you like to eat/look at or alternatively – something you hate buying (like fresh berries) and grow that. I got started with tomatoes because I think the greatest flavor is a fresh tomato picked at peak ripeness still warm from the summer sun. Oh yeah! Once you have chosen the plant or plants you intend to grow look up what the plants enjoy (hint – the majority of vegetable and fruits will prefer full sun in well-drained but moist soil with a pH of 6-7).
A bit on seeds – please buy from good seed dealers. It is very important that you don’t just grab any old packet of seeds from Lowes. Why? Because I want you to save those seeds. A lot of what common vendors sell are hybrids meaning they were a cross between 2 plants and their seed will not produce the same seeds. Plants change with every generation so if you save the seeds from one type of tomato now – you will end up with a different one in 20 years (if you select the best of the crop, the quality will only improve). Good seeds also have higher germination rates, are not treated with anything, have a long and interesting history, and if you select for flavor – will have better flavor! I personally recommend Baker’s Creek seeds. They average around $3 a packet and if you save your seeds every generation that’s a one-time fee. Of course you may just be starting and want to grab that $0.48 packet of lettuce and I cannot stop you, and you will not be poisoned. But as you extend your roots into gardening please research seed saving and the importance of heirlooms.
Depending on what you are planting changes if they should be direct sown or transplanted. Some crops (like berries, cherries, apples, etc) need to be started from a root stock and cutting. Others like asparagus and strawberries are started from crowns. Hence, I cannot give any blanket rules on planting. I can say that as a rule leaf and root crops should be started in the spring and fall/late summer (cool season) and fruiting crops (like zucchini, tomatoes, squash, peppers) should be started indoors and transplanted during the warm season. Just make sure you are always planting in the appropriate season for you plant.
Weeds – A lot of people freak out with weeds. Contrary to popular belief a lot of them actually help the soil. If you don’t remember to plant a cover crop in the spring chickweed may invade your beds. This still holds the soil in place and can be mixed in like any other cover. Research your weeds – some are edible, some are medicinal. Dandelions are fucking magical! If you don’t like something – pull it, don’t spray it. Find a way to fight it with plants or clever covering rather than chemicals. Get rid of the notion that a garden has to be one type of crop and weeds will become your friends.
Of course, I personally am fighting a battle with a grass called Bermuda grass. It has invaded a few of my beds and spreads via runners. It is also allelopathic meaning it hinders the growth of other plants. I do not have an easy solution, but I am trying to plant taller plants to shade them out. Some weeds do just suck, but you need to find a wholesome way to fight them.
Spacing and companion planting:
I don’t really do rows of things and I rarely grow a single crop on its own. You need to learn what works for you, but I enjoy companion planting (planting multiple species together aka polyculture) because it makes for a more interesting garden and helps cover the soil better. A classic and often cited example of this is the “three sisters” practiced by the native Americans. The three sisters are corn, squash, and beans. The corn is planted in a block along with squash, a few weeks later runner beans are planted. The corn grows up and produces its crop, the squash covers the ground to preserve water, and the beans trail up the stalks of corn and their roots also provide nitrogen in the soil. Using this method, you make the plants healthier and produce a lot more food per sq. ft. than if they were grown individually in rows.
**A very important note – Soil should always be covered. Either by a thick blanket of plants or mulch. Sun and wind are huge enemies of the microbes in soil and most of the life in soil resides in the first few cm. Roasting it in full sun will not do your plants any favors. **
This is more a point in conservation rather than function – try not to over water. A lot of gardeners get pumped about driplines and irrigations, but once a plant is established it doesn’t need as much as you think. When you do water you should water deeply and thoroughly, but infrequently. This trains the roots to dive down deeper making a stronger more drought-resistant plant. Of course some plants like pumpkins need a lot of water – this is why research is important.
If you are starting from seed you should really water every day until the plant is at least a few inches high – baby plants need to be babied.